Preheat oven to 375°F.

Spray muffin pans with nonstick spray or line with paper liners.

Use a clean coffee grinder to roughly grind the flax seeds, trying not to process them into a mealy texture. (You can use pre-ground flax if that's what you have on hand.)

Wash and dry the blueberries

In a small bowl, combine the oats and buttermilk, and let stand at room temperature for five minutes.

In a medium bowl, combine the flour, baking powder, baking soda, cinnamon, and salt; mix with a fork to blend and set aside.

In a large bowl and using a hand mixer, beat the egg, applesauce, brown sugar at medium speed for 3 minutes.

Blend in the oat-buttermilk mixture.

Stir in the flour mixture only to combine, try not to overwork the mixture.

Fold in the blueberries.

Fill muffin cups 3/4 full and top with a sprinkle of flax seed.

Bake 15 minutes or until a toothpick inserted into the center comes out clean.