1cupbuttermilk (I used 1 cup milk + 1 tsp lemon juice; let sit 10 minutes before using.)
1/4cupfine breadcrumbs (I used plain panko)
1lbsfresh blueberries (I used 3 cups frozen)
Crumb Mixture:
1/2cupbutter, cold
1cupsugar
1/2cupflour
Instructions
Preheat oven to 375*F. Grease a 11x13" baking pan.
Prepare crumb mixture: In a bowl, cut up cold butter, sugar & flour. Set aside.
In a stand mixer, beat together butter & sugar until light.
Beat in eggs one at a time & add vanilla. Scrape bowl.
In a separate bowl, whisk together flour, salt & baking powder.
On medium speed, mix flour alternating with buttermilk into butter mixture.
Spread cake mix onto greased pan. Evenly coat with breadcrumbs & then top with washed blueberries.
Sprinkle the top with crumb mixture & bake for 20-35 minutes (less time if using fresh blueberries, more time if using frozen blueberries) or until the edges are brown & a toothpick comes out clean from the center. Allow cake to cool before you cut it.