Mexican milk caramel slow-cooked to sweet perfection is a classic confection. This family-friendly treat is a rich, creamy, versatile sweet for desserts and snacking.
In a heavy-bottomed, wide saucepan, combine whole milk and white sugar over medium heat. Stir constantly until the sugar is fully dissolved and the mixture just begins to steam.
Add baking soda to the mixture and immediately reduce heat to a gentle simmer. The baking soda will help prevent scorching and promote caramelization.
Simmer uncovered, stirring every 5–10 minutes. As the mixture thickens and darkens, adjust the heat to the lowest setting to prevent burning, and scrape the bottom and sides regularly.
Continue to cook slowly for 2–2.5 hours. When the mixture reduces by half and turns a deep golden-brown, stir more frequently to maintain a creamy texture and avoid sticking or clumping.
Once a ribbon forms when the dulce de leche is lifted with a spoon and a rich caramel aroma develops, remove from heat. Stir in vanilla extract, then cool and store in a jar.