Blueberry and Sour Cream Muffins

Heat oven to 180 degrees. Add paper liners to two 12-muffins baking trays In a medium size bowl sift flour, baking soda, baking powder, cinnamon and salt. In a large bowl, with electric beaters mix eggs & sugar together till pale yellow. Slowly add the oil till it is all incorporated. Add vanilla and sour cream and beat till smooth. Add flour mix and fold in with a wooden spoon until just combined. Do not overmix or the muffins become tough. Gently stir in the blueberries. Spoon into muffin trays till 3/4 full. Sprinkle each muffin with a little brown sugar to add a crunchy top. Bake for 25 minutes turning once halfway though. Note: you can make the 2 wet and dry mixes the day before and then mix together and add blueberries the next morning for fresh muffins for breakfast.