Ham and Zucchini Recipes: Savory Cheddar Casserole

This ham and zucchini cheddar casserole is a savory, sliceable bake made with grated zucchini, cooked ham, eggs, cheddar, and a little flour. It works as a relaxed brunch dish or an easy dinner because squeezing excess moisture from the squash helps the center bake up tender rather than soggy, while ham and cheese add plenty of savory flavor.

Ingredients

2 lb zucchini (900 g), ends trimmed
1 tsp fine salt (6 g), for drawing moisture from the zucchini
1 tbsp olive oil (15 ml)
1 medium yellow onion, finely diced (about 1 cup or 150 g)
2 garlic cloves, minced (about 6 g)
2 cups diced cooked ham (280 g)
5 large eggs (about 250 g without shells)
1 cup whole milk (240 ml)
1 cup all-purpose flour (125 g)
1 tsp baking powder (4 g)
½ tsp ground black pepper (1 g)
¼ tsp fine salt (1.5 g), for the egg mixture
1½ cups shredded sharp cheddar cheese (170 g), divided
2 tbsp chopped fresh parsley (8 g), plus a little extra to garnish if desired

Instructions

Heat the oven to 375°F (190°C). Lightly oil a 9-by-13-inch (23-by-33-cm) baking dish. Set out a large mixing bowl, a box grater, and a clean kitchen towel or several layers of paper towels. Starting the oven while you prepare the ingredients allows it to reach temperature without adding a separate wait later.
Coarsely grate the zucchini into a colander set over a bowl. Sprinkle it with the 1 teaspoon salt, toss, and leave it to drain for 10 minutes. The salt helps draw out water that could otherwise make the casserole wet. Gather the grated zucchini in the towel and wring it firmly over the sink. Squeeze in batches if needed; it should feel damp, not dripping. The draining time is included in the 30-minute prep estimate.
While the zucchini drains, dice the onion, mince the garlic, chop the parsley, and cut the cooked ham into small, even pieces if it is not already diced. Smaller pieces distribute well through the casserole and make it easier to cut neat portions. Shred the cheddar if using a block; freshly shredded cheese generally melts more evenly than pre-shredded cheese, though either works.
Warm the olive oil in a skillet over medium heat. Add the onion and cook for 4 to 5 minutes, stirring now and then, until softened but not browned. Stir in the garlic and cook for 30 seconds, just until fragrant. Add the diced ham and cook for about 1 minute to take the chill off, then remove the skillet from the heat. This short sauté softens the onion and prevents a raw, sharp flavor in the finished bake.
In the large bowl, whisk the eggs and milk until blended. Add the flour, baking powder, black pepper, and the remaining ¼ teaspoon salt; whisk until no large dry pockets remain. A few small lumps are fine. Fold in the squeezed zucchini, onion and ham mixture, parsley, and 1 cup (about 113 g) of the cheddar. Scrape the bottom and sides of the bowl so the flour and filling are evenly distributed. The mixture will be thick and generously filled with vegetables, rather than pourable like a thin omelet.
Transfer the mixture to the prepared baking dish and spread it into an even layer. Scatter the remaining ½ cup (about 57 g) cheddar across the top. Bake for about 40 minutes, checking near the end. The center should look set rather than liquid, and a food thermometer inserted into the middle should read 160°F (71°C); this is the USDA FSIS safe minimum internal temperature for egg dishes. If the top is browning quickly before the center reaches temperature, loosely cover the dish with foil for the final few minutes.
Set the dish on a heat-safe surface and rest it for 10 minutes before cutting. The rest helps the egg-and-flour base firm up, so portions lift out more cleanly. Sprinkle with extra parsley if you like, then cut into eight pieces and serve warm. The total time includes this resting period.

Tips

Squeeze the zucchini well. This is the key step for avoiding a watery center. After the initial drain, twist the towel until you no longer see water running out. If your zucchini is especially large or seeded, scoop out the soft seed core before grating; it tends to hold more moisture and can make the texture less even.
Use cooked ham and taste before adding more salt. Deli ham, leftover roast ham, and thicker ham steak all work when diced. Their salt levels vary, so keep the measured salt as written at first and avoid adding extra until you taste a baked portion. If the ham is very salty, use a little less and add another handful of zucchini or cheese to keep the filling balanced.
Measure flour lightly. Spoon flour into a measuring cup and level it rather than packing it down. Too much flour can make the casserole dense and dry. The flour and baking powder give the egg mixture enough body to hold the zucchini and ham in slices; this is meant to be a soft savory bake, not a crustless quiche.
Let the center finish before raising the heat. A deep dish or a cold filling can require a few extra minutes. Check the center with a thermometer rather than relying only on a browned top. If the edges are set but the middle is still loose, continue baking in short intervals and cover the surface loosely if needed.

Serving Suggestions

Serve the casserole warm as the centerpiece of a simple meal. For brunch, pair a square with fruit, sliced tomatoes, or a green salad with a light vinaigrette. The fresh, crisp sides balance the soft, savory bake without adding much work. For lunch or dinner, add roasted potatoes, crusty bread, or a bowl of vegetable soup. If serving a crowd, cut the casserole into smaller squares and offer mustard or a spoonful of plain yogurt alongside; both give each bite a bright, tangy contrast.

This bake also works well on a buffet because it can be served warm or at room temperature for a short meal service. Keep it out no longer than two hours, then refrigerate any leftovers. If you are planning a larger spread, bake it close to serving time and allow the required 10-minute rest before cutting. A sharp knife and a thin spatula help lift portions without breaking the tender center.

Variations

Change the cheese: Monterey Jack gives a mild, creamy result, while Swiss or Gruyère brings a nuttier flavor. Use the same total amount as the cheddar. A small amount of Parmesan can be added for a saltier, more savory top, but reduce the added salt if you do.

Make it with another cooked meat: Diced cooked turkey or chicken can replace the ham in the same quantity. Because these options may be less salty, taste the mixture before baking and adjust the seasoning modestly. For a meat-free version, leave out the ham and add 1 cup (about 150 g) of sautéed mushrooms or chopped bell pepper. Cook those vegetables until their moisture has evaporated so they do not make the bake watery.

Add herbs or vegetables: Chives, dill, or a little thyme can replace or complement the parsley. You can add up to ½ cup (about 75 g) of chopped roasted red pepper, but drain it well first. Spinach is another option; wilt it in the skillet and squeeze out excess liquid before folding it in. Keep extra vegetables to a modest amount so the egg mixture still sets properly.

Use a different baking dish: A similar-volume casserole dish can work, but the bake may be thicker or thinner, which changes the cooking time. Begin checking the center around 35 minutes and continue until it reaches 160°F (71°C). A smaller, deeper dish usually takes longer than a 9-by-13-inch pan; do not take it out simply because the top looks browned.

Storage and Reheating

Refrigerate leftovers within 2 hours of baking. Once the casserole has cooled enough to handle, transfer portions to an airtight container or cover the baking dish tightly and refrigerate for 3 to 4 days. Smaller portions cool and reheat more evenly. Do not leave the casserole at room temperature for extended storage, and discard portions that have been left out beyond the two-hour limit.

For the oven, place a portion in an oven-safe dish, cover loosely with foil, and heat at 325°F (163°C) until hot throughout. A microwave is convenient for one serving: cover it loosely and heat in short bursts, turning or rearranging the piece if needed. Reheat leftovers to 165°F (74°C), checking the center with a food thermometer. The casserole can also be frozen in tightly wrapped individual portions for up to 2 months for best quality; thaw overnight in the refrigerator before reheating. Freezing may make the zucchini a little softer, but the portions remain useful for a quick meal.

Frequently Asked Questions

Do I have to salt and drain the zucchini?
It is strongly recommended. Zucchini releases a lot of water as it cooks, and excess liquid can keep the center from setting neatly. Salting it for 10 minutes and squeezing it dry removes much of that moisture. If you skip the salt, still squeeze the grated zucchini firmly, but expect a softer, possibly wetter casserole.

Can I prepare the casserole ahead of time?
You can grate and squeeze the zucchini, dice the ham and onion, and shred the cheese up to a day ahead; store each in a separate covered container in the refrigerator. For the best texture, mix the eggs, milk, and flour shortly before baking, because the zucchini can continue to release moisture while it sits. If you assemble the whole dish ahead, cover and refrigerate it promptly, then bake until the center reaches 160°F (71°C); a cold dish may need extra time.

Can I use frozen zucchini?
Yes, but thaw it completely and squeeze out as much liquid as possible before measuring. Frozen zucchini is generally softer than fresh, so the finished casserole may have a less distinct vegetable texture. Use about 2 lb (900 g) before thawing if it is sold in that quantity, then judge the drained amount by how well it fits into the mixture without making it loose.

How can I tell when the casserole is done without relying on its color?
The most reliable check is a food thermometer placed in the center, which should read 160°F (71°C) for this egg dish. The middle should also look set when gently nudged, not ripple like uncooked liquid. Browning on top is not enough to confirm doneness, since the surface can color before the center is fully cooked.

Why did my casserole turn out watery?
The most common cause is zucchini that was not squeezed firmly enough. Watery ham, vegetables, or a dish that was cut immediately after baking can also contribute. Next time, wring the zucchini in a towel, cook added vegetables until their moisture is gone, and let the casserole rest for the full 10 minutes. If the center is simply undercooked, return the dish to the oven until it reaches the safe temperature.

Can I make it gluten-free?
A cup-for-cup gluten-free baking flour blend can replace the all-purpose flour, provided its package instructions allow it as a direct substitute. The texture may be slightly more tender or crumbly depending on the blend. Check that the baking powder and any packaged ham are labeled gluten-free if that matters for your meal, and still bake the egg mixture to 160°F (71°C).

More recipes to cook

Safety notes: safe minimum internal temperatures from USDA FSIS; raw and undercooked fish guidance from the U.S. FDA. Food safety notes

Spotted an error? Tell us and we will correct it (corrections policy).