Tempering in Cooking: How to Use This Technique

Tempering in cooking means gradually adjusting the temperature of one ingredient by mixing in a small amount of a hotter or colder ingredient before combining them fully. This simple technique is especially useful for smooth custards, sauces, and yogurt-based dishes, preventing eggs from scrambling and dairy from curdling.

Because tempering is a method rather than a finished dish, the guide below demonstrates it with a small vanilla custard sauce. The same gradual-mixing principle applies to many recipes, though the exact amounts and temperatures depend on the ingredients.

Ingredients

2 cups (480 ml) whole milk
4 large egg yolks, about 2.5 oz (70 g)
⅓ cup (67 g) granulated sugar
1 tablespoon (8 g) cornstarch
1 teaspoon (5 ml) vanilla extract
⅛ teaspoon (0.7 g) fine salt

Instructions

Set a fine-mesh strainer over a clean heatproof bowl and place it beside the stove. In a medium bowl, whisk the egg yolks, sugar, cornstarch, and salt until the mixture is smooth and slightly lighter in color, about 1 minute. Breaking up any lumps now helps the finished custard stay silky.
Pour the milk into a medium saucepan. Heat over medium heat, stirring occasionally, until steaming and hot but not boiling, about 4–6 minutes. Small bubbles may form around the edge; remove the pan from the heat before the milk reaches a rolling boil.
Temper the yolks: whisk continuously while slowly pouring about ½ cup (120 ml) of the hot milk into the egg mixture in a thin stream. Take about 30–45 seconds. This gradual addition warms the yolks gently, rather than exposing them all at once to the hot milk. Whisk in another ½ cup (120 ml) of hot milk the same way.
Pour the warmed egg mixture back into the saucepan with the remaining milk, whisking as you go. Set the pan over medium-low heat. Cook, whisking constantly and reaching into the corners of the pan, for 3–5 minutes, until the custard thickens enough to coat the back of a spoon. Do not let it boil: high heat or an unattended pan can cause curdling or scorching.
Remove the pan from the heat as soon as the sauce is thickened. Strain it into the prepared bowl to catch any small cooked bits, then stir in the vanilla. For food safety, egg dishes should reach the USDA FSIS safe minimum internal temperature of 160°F (71°C); check the custard with a food thermometer, taking care that the probe does not touch the pan. If it has not reached that temperature when it thickens, continue heating gently while whisking until it does.
Serve warm, or cool for later use. To cool quickly, set the bowl in a larger bowl of ice water and stir occasionally. If storing, cover the surface directly with food-safe wrap or press parchment against it to limit a skin forming.

Tips

Pour slowly and whisk constantly. A thin stream and steady whisking distribute heat evenly. Adding the hot liquid all at once can cook the yolks into lumps.
Use gentle heat after tempering. Keep the pan at medium-low and do not walk away. A heavy-bottomed saucepan can help reduce hot spots, but it does not replace constant stirring.
Rescue minor lumps. Take the pan off the heat and immediately strain the custard. Straining improves texture, but it cannot undo extensive scrambling or a scorched flavor.
Adjust the thickener thoughtfully. The cornstarch adds stability and body. You can omit it for a thinner, more delicate sauce, but the custard will be easier to overcook and may not thicken as firmly.

Serving Suggestions

Pour the custard warm over fruit, cake, bread pudding, or a slice of pie. It also works as a simple dessert sauce alongside berries or poached pears. For a chilled serving, refrigerate it until cold and spoon it over fresh fruit; the texture will be thicker after chilling.

Tempering is useful well beyond this example. For a hot soup finished with sour cream or yogurt, first whisk a few spoonfuls of hot broth into the dairy, then stir that warmed mixture into the pot off the heat. For a chocolate mixture that needs a smooth finish, follow the recipe’s directions for gradually mixing temperatures rather than pouring cold ingredients directly into a hot base.

Variations

Use a different extract: Replace the vanilla with ½ teaspoon (2.5 ml) almond extract or 1 teaspoon (5 ml) lemon extract. These are concentrated, so start with a small amount.
Add citrus: Stir in 1 teaspoon (5 ml) finely grated lemon or orange zest with the vanilla. Zest adds fragrance without making the custard more acidic.
Make it dairy-free: Substitute 2 cups (480 ml) unsweetened oat or soy beverage for the milk. Choose an unflavored version; the sauce may be thinner and its flavor will vary with the product.
Flavor the milk: Warm the milk with a cinnamon stick or a strip of citrus peel, then remove it before tempering. Avoid boiling, which can intensify flavors and cause the milk to foam over.

Storage and Reheating

Cool the custard promptly and refrigerate it within 2 hours of cooking in a covered container. Keep it refrigerated at 40°F (4°C) or colder and use within 3–4 days. Do not leave it at room temperature for extended periods.

Reheat only the amount you plan to serve, over low heat in a saucepan, whisking constantly until steaming and smooth. Alternatively, microwave in short 15-second bursts, stirring between each. Reheated leftovers should reach 165°F (74°C); avoid boiling, which can make the sauce grainy. If it thickens too much, whisk in a teaspoon or two of milk. Discard custard that has been left out for more than 2 hours.

Frequently Asked Questions

What does tempering mean in cooking?
It is the gradual adjustment of temperature before two ingredients are combined completely. Most often, a little hot liquid is whisked into eggs or dairy to warm them gently, reducing the risk of curdling or scrambling.

Why do eggs scramble when I make custard?
Egg proteins set when heated. If cold or room-temperature eggs meet a large amount of very hot liquid at once, the outside can cook before the mixture warms evenly. Tempering and steady whisking help avoid that sudden temperature change.

How much hot liquid should I add when tempering?
There is no single required amount; follow the recipe. For this custard, add 1 cup (240 ml) of hot milk in two half-cup portions, whisking continuously, before returning the warmed yolks to the pan.

Does tempering mean bringing ingredients to room temperature?
Not usually. In cooking, tempering commonly means gradually changing an ingredient’s temperature by mixing in a portion of a hotter or colder ingredient. In other contexts, such as chocolate work, the term has a different, more specific meaning.

Can I temper eggs without a whisk?
A fork can work for a small quantity if you whisk quickly and pour the hot liquid very slowly. A balloon whisk is more effective at blending the mixture evenly and reducing lumps.

Can I fix custard that has already curdled?
If it has only a few small lumps and is not scorched, immediately remove it from the heat and strain it; an immersion blender may smooth mild graininess. If the eggs are extensively scrambled or the bottom has burned, the texture and flavor are unlikely to recover.

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).