Ingredients:
1 cup butter, at room temperature
2 cups sugar
2 large eggs, at room temperature
1 cup sour cream
1 teaspoon vanilla
2 cups all-purpose flour
1 teaspoon baking powder
1/4 teaspoon salt
1/8 teaspoon baking soda
Topping:
1/4 cup sugar
1 1/2 teaspoons ground cinnamon
Heat oven to 350°. Cream butter at medium speed with an electric mixer until creamy. Gradually add 2 cups sugar, and beat 2 to 3 minutes. Add eggs, 1 at a time, beating well after each addition. Add sour cream and vanilla and beat to combine.
Whisk together flour, baking powder, salt and baking soda. By hand, stir dry ingredients into butter mixture. (Batter will be thick.)
Line muffin pan with muffin cups. Fill each cup 2/3 full with muffin batter.
4. Stir together 1/4 cup sugar and cinnamon. (You may add 1 cup chopped pecans if desired.) Sprinkle topping over batter in muffin cups.
5. Bake muffins at 350° for 20 to 25 minutes or until a wooden pick inserted in the center comes out clean. Remove muffins from pans, and cool completely on wire racks (about 12 to 15 minutes).