preheat oven for 350

spray 9x13 baking dish with nonstick cooking spray

in medium bowl combine bisquick mix and 1/2 cup sugar, add sour cream, eggs, milk and vanilla extract

mix until combined, batter will be very thick

gently stir in blueberries

scoop batter into baking dish and spread out evenly

in small bowl combine the rest of sugar, flour and butter

using your fingers, start combining mixture until it looks coarse and crumbly

sprinkel over dough

bake for 30-35 minutes