Preheat oven to 375°F and lightly grease a 7 x 11 inch pan.
Mix thoroughly sugar, shortening and egg.
Stir in milk.
In a separate bowl sift together flour, baking powder and salt. Then gradually stir into the rest of the mixture.
Carefully fold in blueberries.
Pour mixture into baking dish.
Streusel
Mix sugar, cinnamon and 1/3 cup of sifted flour together.
Cut chilled butter into slices over top of the dry mixture. Use a pastry cutter or fork to blend together until pieces of butter are no bigger than peans.
Sprinkle crumb mixture over top of batter and bake for 40 - 45 minutes until a cake tester comes out clean.