You know you’re on the right track if your most trusted recipe sources agree on procedures for classics such as this one. This recipe for dulce de leche, a thick caramelized milk sauce essential in South American desserts, is adapted from Alton Brown, Saveur, and Wayne Gisslen.
While the instructions and cooking times differ slightly, all three sources agree on the use of baking soda, a key ingredient which may be a bit unexpected. The baking soda tips the slight acidity of milk towards alkalinity. This is important for two reasons (excuse me while I put on my lab coat):
- Alkalinity keeps milk proteins from curdling
For the same reason adding vinegar to milk makes cheese, mildly acidic milk, along with heat, may cause grittiness when milk proteins solidify. Adding the baking soda controls curdling to a certain degree, giving you a smoother dulce de leche.
- Alkalinity helps with browning
Since dulce de leche is all about caramelization, a little help with getting that deep brown hue can’t hurt. One reason pretzels and bagels are boiled in a lye solution is the alkalinity of the liquid — it helps brown the crust while baking.
Dulce de Leche (Spanish)
Doce de Leite (Portuguese)
Confiture de Lait (French)
Caramelized Milk Sauce
makes about 1 cup / 250 ml
4 cups / 1000 ml whole milk
1 1/2 cups / 375 ml granulated sugar
1/2 tsp baking soda
1 vanilla bean, split OR 1/2 tsp vanilla extract
- In a heavy saucepan, combine the milk, sugar, and baking soda.
- Slowly bring to a boil over medium heat without stirring. A foamy layer will develop on top as it reaches a boil.
- Remove from the heat when it reaches a boil. Skim the foamy layer on top and return to the stovetop over medium heat.
- If using the split vanilla bean, add it at this point.
- Continue to simmer gently for 1 hour over medium heat, skimming the top as needed and stirring occasionally.
- If using the split vanilla bean, remove and discard it at this point.
- Continue to simmer gently for 1 to 1 1/2 hours over medium heat, stirring often. Once the dulce de leche reaches a deep caramel color and thick consistency, watch it closely. Stir continuously to prevent the bottom from scorching.
Watch out for scorching when it gets to this stage
- Reduce the heat to low when dragging a spatula across the bottom of the pan leaves trails.
- Fine-tune the consistency to your liking at this point, keeping in mind that dulce de leche will stiffen slightly as it cools. You can thin dulce de leche by adding small amounts of water if it gets too thick.
- Strain the dulce de leche.
- If using vanilla extract, add it at this point.
- Cool to room temperature before storing.
Dulce de Leche Storage:
Refrigerated in an airtight container, dulce de leche will keep for up to a month (as if it will last that long).