• ½ cup unsalted butter softened  • 8 oz cream cheese softened (full fat) • 1 ¼ cup granulated sugar • ¼ cup light brown sugar tightly packed  • 2 large eggs • 1 teaspoon vanilla extract • 2 ½ cups all-purpose flour • 2 teaspoons baking powder • 1 Tablespoon cornstarch • ¾ teaspoon salt • 1/2 cup buttermilk  • 2 ¼ cup blueberries

Streusel Topping (optional) •  1 ⅓ cup all-purpose flour • 1 cup + 2 Tablespoons light brown sugar firmly packed • ¼ cup all-purpose flour  • ¼ tsp salt • 10 Tablespoons unsalted butter (melted and cooled , no longer hot)

Preheat oven to 350F (175C). Then, combine butter, cream cheese, and sugars and use an mixer to cream together ingredients until well-combined. 

Add eggs and vanilla extract and beat on medium-low speed until combined, pausing to scrape the sides and bottom of the bowl.

In separate bowl whisk together flour, baking powder, cornstarch and salt.

Add about 1/4 of the flour mixture and stir on low speed until just combined. Add about 1/3 of the buttermilk and stir.  Continue to alternating until all are added & combined.

Use a spoon or spatula to stir in the blueberries.

Lightly grease and flour a 13×9 baking pan. Then, spread batter into prepared pan (batter will be thick) and prepare streusel, if using.

To make streusel, whisk together flour, sugars, and salt. Drizzle in melted butter and use a fork to stir/toss together until mixture is clumpy but combined (all the butter should be absorbed).

Sprinkle streusel evenly over batter. Then, bake on 350F for 55-60 minutes or until a toothpick inserted in the center yields moist crumbs. 

Allow to cool before serving. Then, enjoy!