Position knife blade in food processor bowl. Add first 3 ingredients; process 5 seconds or until mixture resembles fine meal. Add margarine, and pulse 5 times or until mixture resembles coarse meal. Transfer to a small bowl, and stir in chopped almonds. Set aside.
Combine 2 cups flour and next 5 ingredients in a large bowl. Add blueberries; toss gently to combine. Make a well in center of mixture. Combine buttermilk, oil, and egg; add to dry ingredients, stirring just until dry ingredients are moistened.
Spoon batter into muffin pans coated with cooking spray, filling two-thirds full. Sprinkle evenly with oat mixture. Bake at 400° for 15 to 20 minutes or until muffins are golden. Remove from pans immediately.