CINfully Delicious Chocolate Cupcakes

1 (18.25 ounce) package chocolate cake mix

1 cup milk

3 eggs

½ cup butter, melted

1 teaspoon ground cinnamon

1 teaspoon vanilla extract

1 teaspoon cinnamon sugar, or as needed

½ cup butter

½ cup butter-flavored shortening

1 pinch sea salt

1 teaspoon vanilla extract

1 tablespoon ground cinnamon

1 tablespoon unsweetened cocoa powder

3 cups confectioners sugar

¼ cup milk

2 cups confectioners sugar, or more as needed

Preheat an oven to 350 degrees F (175 degrees C).

Line 24 muffin cups with paper liners.

Beat together the chocolate cake mix, 1 cup milk, eggs, 1/2 cup melted butter, 1 teaspoon cinnamon, and 1 teaspoon vanilla extract in a bowl with an electric mixer on low speed until moist. Beat for 2 more minutes on medium speed.

Fill each muffin cup about 2/3 full of batter.

Sprinkle the cupcakes with cinnamon sugar.

Bake in the preheated oven until a toothpick inserted into the center comes out clean, about 15 minutes.

Cool in the pans for 10 minutes before removing to cool completely on a wire rack.

Cream together 1/2 cup butter and shortening in a bowl until smooth.

Stir in sea salt, 1 teaspoon vanilla extract, 1 tablespoon cinnamon, cocoa powder, and 3 cups confectioners sugar.

Stir in milk.

Mix in 2 more cups confectioners sugar or as needed until desired consistency is achieved.

Spread the frosting on the cooled cupcakes.