La Lechera is a specific brand of sweetened condensed milk, which contains milk and sugar in its list of ingredients. A popular recipe for homemade sweetened condensed milk can be made by combining sugar, powdered milk, boiling water and melted butter in a blender and processing until smooth.
While La Lechera and other sweetened condensed milks are commercially produced and sold in many grocery stores, the oft-used baking ingredient can be home-made according to the type of recipe—quickly prepared, unprocessed or low caloric value—one wishes to use. Most recipes recommend refrigerating any homemade condensed milk to preserve freshness.
Paula Deen's popular recipe involves blending 1/3 cup boiling water, 3/4 cup of sugar, 4 tablespoons of butter and 1/2 teaspoon of vanilla extract before adding 1 cup of powdered milk to thicken the mixture.
To dial back the calories inherent in traditional sweetened condensed milk one can use a popular recipe found on Food.com that involves heating a mixture of cold water and nonfat powdered milk then adding sugar and vanilla.
To make sweetened condensed milk using whole ingredients, one can heat a mixture of whole milk and unrefined, organic sugar over low heat until the sugar is dissolved and the liquid is reduced by half. Add butter and vanilla extract to the reduction to complete the recipe.