Sweetened condensed milk
Brown sugar
Butter
Vanilla extract
Icing sugar, sifted
Line a 8.5 x 4.5-inch (22 cm x 12 cm) rectangular baking dish with wax paper or parchment paper.
Mix together all the ingredients except the icing sugar.
Cook the preparation in the microwave for 10 minutes, stirring each 2 minutes.
Incorporate the icing sugar and mix for 10 minutes using a hand mixer or stand mixer. Pour the preparation into the baking dish and refrigerate a minimum of 8 hours.
