Pre-heat the oven to 350F. Line 12 cupcake tins with paper or grease with butter and flour.
Mix 1/4 cup granulated sugar and 2 teaspoons of cinnamon and sprinkle evenly over each cupcake.
I also used these Dulce de Leche Donuts to top these cupcakes.
You will have some leftover dulce de leche most likely. You can store it in the freezer for up to 2 months, or in the fridge for 3-4 weeks.