Blueberry coffee cake

Ingredients:

For the Streusel Topping:
1 c all-purpose flour
1/2 c granulated sugar
1/3 c packed brown sugar
1 1/2 tsp cinnamon
1/2 c unsalted butter, melted

For the Blueberry Cake:
1 1/2 c all-purpose flour
2 tsp baking powder
1/4 tsp  baking soda
1/4 tsp  salt
6 Tbsp butter, softened
3/4 c granulated sugar
2 eggs
2 tsp vanilla extract
1/3 c sour cream or Greek yogurt
1/3 c buttermilk**
1 1/4 c fresh blueberries (if using frozen berries do not thaw first)
2 tsp flour

For the Vanilla Glaze:
1 c powdered sugar
1 1/2 tablespoons milk

Instructions:

Make the Streusel -
In a medium-sized bowl whisk together the flour, sugars and cinnamon. Then stir in the melted butter with a spatula or spoon. The mixture should look like wet sand

Make the Cake-
Preheat the oven to 350 degrees. Grease and lightly flour the bottom and sides of a 9 inch springform pan (pie plate can be used as a substitute).

In a medium-sized bowl whisk together the flour, baking powder, baking soda and salt.

In a separate large bowl using an electric mixer on medium speed, beat the butter and sugar together until fluffy. Then add in the eggs and vanilla and continue mixing until evenly combined. Beat in the sour cream, followed by the flour mixture. Scraping the bowl as necessary, then carefully beat in the buttermilk. Be careful not to overmix the batter. 

In a medium bowl, toss the blueberries with 2 tsp flour. Then gently stir into the cake batter using a large wooden spoon or rubber spatula. 

Pour the batter into the prepared pan, then crumble the streusel mixture over top. Bake in the preheated oven for 50 - 55 minutes or until an inserted toothpick comes out clean or with a few cake crumbs, or when you give the pan a gentle nudge the cake doesn't wobble. If you notice the top starting to get brown around 45 minutes, you can tent a piece of tin foil and place it over top.

Allow to cool fully in the pan. 

Make the Glaze-
In a small bowl, whisk together the powdered sugar and milk. Add a little extra milk or powdered sugar as needed. 

Serve-
Once the cake is fully cool, trace around the sides of the pan with a thin knife then unclamp the springform pan. Cut into slices, and drizzle each piece with the glaze. 

Notes:

**If you don't have buttermilk, add 1 teaspoon of distilled vinegar to 1/3 cup of milk and allow to sour for 5 minutes before using.

Leftovers can be stored in an airtight container at room temperature for 2 days, or in an airtight container in the fridge for up to 4 days.