Lemon Blueberry Muffins w/ Streusel Topping

For years, I have been thinking about trying to recreate the Lemon Blueberry muffins from the bakery I used to work at in Arizona. They were my dad's favorite, so when visiting him over Memorial Day, I broke out my new favorite toy (a KitchenAid mixer) to give it a shot.

Since I don't have the original BreadCrafter's recipe, I modified and combined a few different ones I found online ... thankfully, they were a success! Really moist, not too lemony, and my dad seemed to love them ;)

Lemon Zest Strudel Topping
1/2 c. flour
1 tsp. cinnamon
1/2 c. brown sugar
2 tbs. lemon zest
4 tbs. butter (cut into squares)

Directions
In a medium bowl, stir together the flour, cinnamon, zest, and brown sugar. Add the butter pieces and combine the mixture with a fork until the topping resembles coarse crumbs. Set aside.

Muffins
2 1/2 cups all-purpose flour
2 teaspoons baking powder
1/2 teaspoon baking soda
1/2 teaspoon kosher salt
12 tablespoons (1 1/2 sticks) unsalted butter, at room temperature
1 1/2 cups sugar
3 large eggs, at room temperature
1 1/2 teaspoons pure vanilla extract
8 ounces sour cream
1/4 cup milk
1/4 cup lemon juice
3 cups (1 1/2 pints) fresh blueberries, stems removed

Directions
Preheat oven to 350°F. Place paper liners in muffin pans.
In a separate medium bowl, sift together flour, baking powder, baking soda, and salt.
With an electric mixer fitted with a paddle attachment, cream the butter and sugar until light and fluffy, about 5 minutes.
At low speed, beat one egg in at a time, then add vanilla, sour cream, lemon juice, and milk until combined.
Add 1/3 of dry ingredients at a time and beat until just combined.
With a spatula, evenly fold blueberries into batter.
Scoop batter into muffin pans and fill each cup to the top.
Sprinkle topping evenly over batter.
Bake for 30 to 35 minutes.

Recipe bases courtesy of Ina Garten & SundayNiteDinner.com