Spread batter into a greased and floured 9" x 13" pan.
05For topping, in smaller mixing bowl, blend sugar, flour, and cinnamon.
06Blend in softened butter or margarine, making a struesel-type mixture. Sprinkle crumb mixture evenly on top of batter.
07Place pan in oven preheated to 375 degrees and bake for 1 hour or until buckle tests done when tested with a toothpick (pick inserted and pulled from cake will not come out wet). Blueberry Buckle keeps well and is best served warm.