Coffee cake muffins with a sweet cinnamon layer and buttery crumb topping. An easy breakfast or brunch favorite that tastes just like classic coffee cake.
Heat oven to 375°F. Line a 12-cup muffin tin with paper liners or grease well.
Make streusel topping by combining flour, brown sugar, and cinnamon in small bowl. Add melted butter and stir with fork until crumbly. Set aside.1/2 cup all-purpose flour,1/2 cup packed light brown sugar,1 teaspoon ground cinnamon, 1/4 cup unsalted butter.
In large bowl, whisk together flour, sugar, baking powder, baking soda, salt, and cinnamon. 2 cups all-purpose flour,3/4 cup granulated sugar,2 teaspoons baking powder,1/2 teaspoon baking soda,1/2 teaspoon salt,1 teaspoon ground cinnamon.
In medium bowl, whisk together eggs, sour cream, melted butter, and vanilla until smooth. 2 large eggs,1 cup sour cream,1/2 cup unsalted butter,1 teaspoon vanilla extract.
Pour wet ingredients into dry ingredients and stir until just combined. Do not overmix.
Divide half the batter evenly among muffin cups. Sprinkle half the streusel topping over batter in each cup.
Top with remaining batter, then sprinkle remaining streusel topping over each muffin.
Bake 18-20 minutes until golden brown and a toothpick inserted in center comes out clean.
Let cool in pan 5 minutes before transferring to wire rack.
Notes
Don't over mix the batter! Stir just until the flour disappears. Over mixing makes tough, dense muffins.