Preheat your oven to 350°F (177°C). Line a 12-cup muffin tin with cupcake liners.

Mix Dry Ingredients:** In a medium bowl, whisk together the flour, baking powder, baking soda, and salt. Set aside.

In a large microwave-safe bowl, melt the butter in the microwave. Add 1 cup of sugar and whisk until the mixture is gritty. Allow it to cool slightly. Stir in the egg, yogurt, milk, and vanilla extract until the mixture is smooth. Gradually mix in the dry ingredients until the batter is thick and smooth.

In a small bowl, mix the remaining 1/2 cup of sugar with 2 teaspoons of cinnamon. Set aside.

Spoon about 2 scant tablespoons of batter into each cupcake liner. Sprinkle 1 teaspoon of the cinnamon-sugar mixture over the batter. Add another heaping tablespoon of batter on top, filling each liner about 3/4 full. Some cinnamon-sugar filling may show through the top layer. Sprinkle an additional teaspoon of the cinnamon-sugar mixture on top of each cupcake.

Bake the cupcakes for 19-21 minutes or until a toothpick inserted into the center comes out clean. Let them cool completely before frosting.

Frosting Instructions

Using a handheld or stand mixer fitted with a paddle or whisk attachment, beat the butter on high speed until smooth and creamy, about 1 minute.

If the frosting is too thin, add more confectioners' sugar. If it is too thick, add more cream. Taste and add a pinch of salt if the frosting is too sweet (typically about 1/4 teaspoon).