Satisfy your sweet tooth with these brown sugar cupcakes stuffed with dulce de leche and topped with buttercream frosting. It's the perfect dessert for Cinco de Mayo!
Preheat the oven to 350° F. Line a cupcake pan with baking cups.
In a medium bowl, whisk together flour, baking powder, baking soda and salt. Set aside.
In a large mixing bowl with an electric mixer, beat together the butter and brown sugar until light and creamy, about 2 minutes.
Add the eggs one at a time, beating well after each addition. Beat in the vanilla extract, sour cream and vegetable oil. Scrape down the sides and bottom of the bowl as necessary.
Gradually add in the flour mixture in three parts, alternating with milk (So it goes flour, milk, flour, milk, flour). Mix until batter is uniform and smooth (do not over mix).
Fill baking cups about 3/4 full and bake for 15 minutes, or until a toothpick inserted into the center comes out clean. Remove from the oven, transfer cupcakes to a wire rack and allow them to cool to room temperature.
Frosting
In the bowl of a stand mixer, beat the butter using the paddle attachment (whisk attachment works too) until creamy, about 2 minutes. With the mixer on low speed, gradually add in the confectioners' sugar until completely incorporated.
Add the dulce de leche and pinch of salt. Mix until combined. If the frosting is too thick, add 1 to 2 tablespoons of milk. If it’s too thin, add more confectioners’ sugar. Transfer frosting to a piping bag with desired tip.
Assembly
Use a cupcake corer or the large end of a frosting tip to create a shallow hole in the center of the cupcakes. Fill each hole to the brim with about 1 to 2 teaspoons of dulce de leche.
Frost cupcakes and garnish with an additional drizzle of the sauce if you have extra. Serve.
Notes
Dulce de Leche: You will need one 14 ounce can. It's usually found in the baking aisle near the sweetened condensed milk or in the international foods aisle at your local grocery store.Store cupcakes in an airtight container at room temperature for 3 days or in the refrigerator for 5 days.Freeze unassembled cupcakes for up to 3 months. Wrap in plastic wrap and place in an airtight container. Defrost in the refrigerator before bringing to room temperature and frosting.