2cupsmixed berries, fresh or frozen (if using frozen, do not thaw)
1tablespoonflour, if using frozen berries
Preheat the oven to 425F degrees. Line with muffin papers or butter and flour two 12-cavity muffin pans. I ended up with 15 muffins total.
In a large bowl beat the butter and sugar until light and fluffy. Add in the eggs and vanilla and continue beating until combined.
Turn off the mixer. Fold in the lemon zest, sour cream and milk using a large rubber spatula or wooden spoon.
In a separate medium sized bowl, whisk together the flour, baking powder & salt. Gently fold the dry ingredients into the wet until almost combined. The batter will be very thick.
If using frozen berries - toss the berries with 1 tablespoon of flour. Then gently fold the berries into the muffin batter.
Fill muffin cavities to the top (about 1/3 cup batter). Bake at 425F for 5 minutes then turn down the oven to 375F and continue baking for 10-13 minutes. The tops should be just starting to brown and an inserted toothpick should come out clean.
Let muffins cool in the pan for 5-10 minutes. Then remove and continue cooling on a wire rack.