Cinnamon streusel muffins are wonderfully soft and light with a sugary cinnamon twist and crunchy topping. They are truly delicious and very simple to make.
In a large mixing bowl, use a hand mixer to combine ¾ cup of butter with the granulated sugar on a medium speed. Mix until the ingredients are fully combined.
Add the milk, sour cream, eggs, and vanilla to the mixing bowl. Whisk until the added ingredients are fully incorporated into the mixture.
Gently whisk in the baking powder, baking soda, flour, and cinnamon with the wet ingredients. Ensure that no clumps of flour or other dry ingredients remain in the mixture.
Make the streusel topping
In a small saucepan, melt the butter and remove from heat. Stir in the brown sugar and remaining cinnamon. Mix until fully combined.
Fill a muffin tin with liners and divide the batter evenly among 12 liners and sprinkle the top of each muffin with a generous amount of the streusel topping.
Bake the muffins in the preheated oven for 18 minutes.
Serve & enjoy!
Notes
Leftover muffins can be stored in an airtight container on the counter for up to 5 days or in the fridge for 6 days.
You can also store these muffins in the freezer for up to 2 months. Frozen muffins are best thawed on the counter or in the fridge and then warmed in the microwave for about 20 seconds.