Ingredients
Method
- Make the streusel: combine brown sugar, flour, cinnamon, salt, and cold butter with fingertips until clumpy. Chill.
- Whisk flour, baking powder, baking soda, and salt in a bowl.
- Beat butter and sugar until fluffy, 2 minutes. Beat in eggs one at a time, then vanilla.
- On low speed, alternate adding the flour mixture and sour cream until just combined.
- Scoop batter into a lined 12‑cup muffin tin. Top with chilled streusel. Bake at 350°F for 18–22 minutes. Cool in pan 5 minutes, then transfer to a rack.
- Dust with powdered sugar and serve warm.
Notes
For the best rise, all ingredients should be close to room temperature. The streusel stays crunchier if you do not overmix it. If you forget to chill it, pop the whole bowl in the freezer for 5 minutes before using.
