1. Preheat oven to 350 degrees Fahrenheit.
2. In a bowl, mix together the oil, sugar, eggs, orange juice, and vanilla. Add flour and baking powder. The batter will be very thick.
3. Gently fold in the blueberries.
4. Pour batter into mini muffin tins (I used a cookie scoop).
5. In a bowl, mix together crumb ingredients (crumbs will seem very wet). Crumble over muffins.
6. Bake for 15 minutes.