Equipment
Ingredients
Roux Base
- 40 g unsalted butter, cubed
- 40 g all-purpose flour
Dairy
- 400 ml whole milk, cold
Cheese and Seasonings
- 80 g gruyere cheese, freshly grated
- 40 g parmesan-style cheese, freshly grated
- 1 g ground nutmeg
- fine sea salt
- white pepper
Nutrition (per serving)
Nutrition is estimated per serving. Nutrients without complete source data are omitted.
Full nutrition
- Calories
- 146 kcal
- Protein
- 7 g
- Carbohydrates
- 7 g
- Fat
- 10 g
- Fiber
- 0 g
- Sugar
- 3 g
- Sodium
- 250 mg
- Saturated Fat
- 6 g
- Monounsaturated Fat
- 3 g
- Polyunsaturated Fat
- 0 g
- Cholesterol
- 30 mg
- Potassium
- 86 mg
- Calcium
- 219 mg
- Iron
- 0.2 mg
- Magnesium
- 12 mg
- Phosphorus
- 144 mg
- Zinc
- 0.8 mg
- Vitamin A
- 95 mcg
- Vitamin C
- 0 mg
- Vitamin D
- 0.7 mcg
- Vitamin E
- 0.2 mg
- Vitamin K
- 1 mcg
- Vitamin B6
- 0.0 mg
- Vitamin B12
- 0.5 mcg
- Thiamin
- 0.04 mg
- Riboflavin
- 0.13 mg
- Niacin
- 0.1 mg
- Folate
- 5 mcg
- Water
- 50 g
Sources: USDA FoodData Central
Method
Place the saucepan over medium heat and add the butter, allowing it to melt completely without browning.
Add the flour to the melted butter and whisk continuously for 1 to 2 minutes until it smells lightly toasted but remains pale, creating a white roux.
Pour in the cold milk in a slow, steady stream while whisking vigorously to incorporate the roux and prevent lumps from forming.
Bring the mixture to a gentle simmer around 90C or 195F. Cook for 4 to 5 minutes, whisking frequently, until the sauce thickens enough to heavily coat the wires of your whisk.
Remove the saucepan from the heat completely. Add the grated Gruyere and Parmesan cheeses in small handfuls, stirring gently until completely melted and the sauce is perfectly smooth.
Stir in the ground nutmeg, salt, and white pepper. Taste and adjust the seasoning as necessary.
Chef's Notes
- Always grate your own cheese from a fresh block. Pre-grated cheeses are coated in starches and anti-caking agents that will make your velvety sauce feel grainy.
- Using cold milk into a hot roux is a classic culinary school technique. The temperature difference prevents the flour starches from swelling too rapidly, which is the primary cause of lumpy bechamel.
- White pepper is traditional in white sauces purely for aesthetic reasons to avoid black specks. If you do not mind the visual difference, freshly ground black pepper offers a superior, more robust flavor.
- If using this sauce for a baked macaroni and cheese, you want the Mornay to be slightly looser than you think it should be, as the pasta will continue to absorb moisture as it bakes.
Storage
Refrigerator: 3 days — Press plastic wrap directly onto the surface of the sauce to prevent a skin from forming.
Freezer: 1 month — Texture may become grainy upon thawing. Reheat gently and blend with an immersion blender to restore smoothness.
Reheating: Reheat gently on the stovetop over low heat, whisking constantly. Add a splash of milk if the sauce has thickened too much.
Troubleshooting
Sauce turned out lumpy
Cause: Milk was added too quickly or whisking was insufficient while incorporating the liquid into the roux.
Fix: Remove from heat and process with an immersion blender until smooth, or pass through a fine mesh sieve.
Prevention: Add the milk in very small increments at first, whisking until completely smooth before adding more.
Sauce is grainy or split
Cause: The sauce was returned to a boil after the cheese was added, causing the dairy proteins to coagulate.
Fix: Whisk in a tablespoon of cold milk off the heat vigorously to help re-emulsify. If heavily split, it cannot be completely fixed.
Prevention: Always remove the bechamel from the heat completely before folding in the cheese, and never boil it again.
Cultural Context
Mornay sauce is a celebrated derivative of bechamel, one of the five grand mother sauces of French cuisine codified by Auguste Escoffier. Originally created in the late 19th century and named after the Marquis de Mornay, it traditionally relies on the deep, nutty profile of Alpine cheeses like Gruyere to transform a simple white sauce into a rich, decadent binding component.
