Open-Face Roast Beef Sandwich with Gravy

An open-face roast beef sandwich layers tender roast beef over toasted bread and covers it with warm, savory gravy. This hearty, knife-and-fork meal comes together quickly with cooked roast beef, whether it is freshly roasted or sliced from the deli, and is easy to customize with vegetables or cheese.

Ingredients

4 thick slices sourdough or country bread, about 1 inch (2.5 cm) thick, 8 oz (225 g) total
1 tbsp (15 ml) olive oil or 1 tbsp (14 g) softened butter, for the bread
2 tbsp (28 g) unsalted butter
1 small yellow onion, thinly sliced, about 1 cup (150 g)
2 tbsp (16 g) all-purpose flour
2 cups (475 ml) low-sodium beef broth
1 tsp Worcestershire sauce (5 ml)
½ tsp dried thyme (about 0.5 g)
¼ tsp freshly ground black pepper (about 0.5 g), plus more to taste
1 lb (450 g) cooked roast beef, thinly sliced
½ cup (75 g) frozen peas, thawed (optional)
¼ tsp kosher salt (about 1.5 g), or to taste; broth and beef may already be salty
2 tbsp (8 g) chopped fresh parsley, for serving (optional)

Instructions

Toast the bread. Heat the oven to 400°F (200°C). Arrange the bread on a baking sheet and brush both sides lightly with olive oil or softened butter. Bake for 8–10 minutes, turning once, until lightly crisp at the edges and still sturdy enough to hold gravy. Set aside. You can also toast the bread in a skillet or toaster.
Soften the onion. While the bread toasts, melt the butter in a medium saucepan over medium heat. Add the sliced onion and cook for 5–6 minutes, stirring occasionally, until soft and beginning to turn golden. Lower the heat if the onion starts browning too quickly.
Make the gravy base. Sprinkle the flour over the onions and stir for 1 minute to coat them and cook off the raw flour taste. Slowly whisk in the beef broth, scraping the bottom of the pan to loosen any browned bits. Add the Worcestershire sauce, thyme, and black pepper.
Simmer the gravy. Bring the mixture to a gentle simmer, whisking frequently, then cook for 4–5 minutes until thick enough to coat a spoon. Stir in the peas, if using, and simmer for 1 minute. Taste before adding salt; add a small amount if needed. If the gravy becomes too thick, whisk in broth 1 tablespoon (15 ml) at a time.
Warm the roast beef. Add the sliced beef to the gravy and gently separate the slices with tongs or a fork. Heat over low to medium-low for 2–3 minutes, just until steaming hot throughout. Avoid a hard boil, which can make already-cooked beef tough. If measuring, USDA FSIS advises reheating leftovers to 165°F (74°C); check the center of the beef with a food thermometer. Deli-sliced beef should also be heated to 165°F (74°C), particularly for people at higher risk from foodborne illness.
Assemble and serve. Place one slice of toast on each plate. Divide the beef and gravy among the slices, spooning extra gravy over the bread. Finish with parsley and serve immediately while hot.

Tips

Choose sturdy bread. Thick-cut sourdough, country bread, or Texas toast holds up better than thin sandwich bread. Toasting helps keep the center from becoming soggy too quickly.
Keep the beef tender. Use thin slices and warm them gently in the finished gravy. If using freshly roasted beef, slice it across the grain; that shortens the muscle fibers and makes each bite easier to chew.
Adjust the gravy texture. For thinner gravy, add broth gradually. For thicker gravy, simmer it a little longer before adding the beef. Avoid adding flour directly to hot gravy, since it can form lumps; whisk flour with the butter and onions first.
Mind the salt. Roast beef, broth, and Worcestershire sauce can all be salty. Start with low-sodium broth, taste the gravy, and season only at the end.

Serving Suggestions

Serve the sandwich with a crisp green salad, steamed green beans, or roasted carrots to balance the rich gravy. For a classic diner-style plate, add mashed potatoes or oven fries; the potatoes are especially good with any extra gravy. A sharp pickle or a spoonful of horseradish on the side gives the beef a bright, peppery contrast.

Variations

Cheesy version: Add a slice of provolone or Swiss over the beef and briefly broil until melted. Keep the bread on an oven-safe plate and watch closely so the toast does not burn.

Mushroom gravy: Replace the onion with 6 oz (170 g) sliced mushrooms, or cook the mushrooms with the onion. Let them brown before adding flour for a deeper, more savory gravy.

Horseradish finish: Spread 1–2 tsp (5–10 g) prepared horseradish on each piece of toast before adding the beef. It adds a sharp bite; use less for a milder sandwich.

Use leftover roast: Thinly slice leftover cooked beef and follow the recipe as written. If the beef is already well-seasoned, taste the gravy before adding salt. For a vegetarian alternative, use vegetable broth and sautéed mushrooms instead of beef; the result is a mushroom gravy toast rather than a roast beef sandwich.

Storage and Reheating

For best texture, store the beef and gravy separately from the toast. Refrigerate leftovers within 2 hours of cooking in shallow, airtight containers; cooked roast beef and gravy keep for 3–4 days in the refrigerator at 40°F (4°C) or colder. Do not leave the assembled sandwich at room temperature for more than 2 hours, or 1 hour if the temperature is above 90°F (32°C).

Reheat the beef and gravy together in a covered saucepan over low heat, stirring occasionally and adding a splash of broth if needed. Heat leftovers to 165°F (74°C), checking the center with a food thermometer. A microwave also works: cover loosely, heat in short intervals, and stir between intervals so the beef warms evenly. Toast fresh bread for serving rather than reheating assembled sandwiches. Freeze the beef and gravy in a freezer-safe container for up to 2–3 months for best quality; thaw overnight in the refrigerator and reheat to 165°F (74°C).

Frequently Asked Questions

Can I use deli roast beef?
Yes. Choose thinly sliced roast beef from the deli and warm it gently in the gravy. For food safety, heat deli-sliced beef to 165°F (74°C), especially when serving someone who is pregnant, older, very young, or immunocompromised.

What cut of bread works best?
Thick slices of sourdough, country bread, or a rustic white loaf work well because they support the beef and gravy. Toast them until lightly crisp, not hard, so they remain easy to cut with a fork and knife.

Can I make the gravy without flour?
For a gluten-free option, use 1½ tbsp (12 g) cornstarch mixed with 2 tbsp (30 ml) cold water. Whisk the slurry into simmering broth and cook until glossy and thickened. Use broth and Worcestershire sauce labeled gluten-free if needed.

Why did my gravy turn lumpy?
Lumps usually form when flour is added to liquid too quickly or without being mixed into fat first. Cook the flour with the butter and onion, then whisk in broth gradually. If lumps remain, strain the gravy or blend it briefly before adding the beef.

Can I make the components ahead?
Yes. Make the gravy up to 3 days ahead and refrigerate it promptly. Reheat it gently, add the beef, and heat to 165°F (74°C); toast the bread just before assembling so it stays crisp.

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).