2. In a large mixing bowl, combine 2 cups self-rising flour and 1/3 cup sugar. Make a well in the center of the flour-sugar mixture.
3. In a medium mixing bowl, combine 1 well-beaten egg, ¾ cup milk, and ¼ cup vegetable oil.
4. Add liquid mixture to the dry mixture. Stir just until dry ingredients are moistened. Do not over-stir. 5. Combine 1 cup fresh blueberries with reserved 2 tablespoons of flour-sugar mixture. Toss to coat. Fold coated blueberries gently into muffin batter.
6. Spray 12 muffin tins with cooking oil spray. Spoon batter into muffin tins, filling each ¾-full.
7. In a small bowl, combine ¼ cup brown sugar and 2 tablespoons flour. Cut in 1 tablespoon butter, using a pastry blender or fork. Mixture should be crumbly. Spoon mixture evenly over the batter in the 12 muffin tins.
8. Bake for approximately 18 minutes, or until lightly browned.
9. Remove from pan and place on a nice serving plate and serve.