01Preheat oven to 350 F. Line a muffin tin with paper or silicone liners, set aside.
02In a small bowl, stir together cinnamon and sugar for cinnamon sugar topping, set aside.
03In a medium bowl, use an electric mixer to combine the butter and sugar until fluffy. Add the egg, milk, vanilla and yogurt to combine.
04In a separate bowl, whisk together flour, baking powder, baking soda, cinnamon and salt.
05Add flour mixture to butter mixture until flour is incorporated.
06Divide the batter evenly between the muffin cups and sprinkle with half of the cinnamon sugar topping. Bake for 20-25 minutes or until a toothpick inserted into the center of the muffin comes out clean.
07Meanwhile, in a large bowl or stand mixer add all the ingredients for the Yogurt Frosting and mix until creamy and smooth, set aside.
08Once muffins are done, remove from oven and transfer to a wire rack to cool completely. Once cool, top with frosting and sprinkle with remaining cinnamon sugar.