Combine oats and buttermilk in a large mixing bowl. Let stand 30 minutes.
Sift together - steel blade. Measure in: brown sugar, baking powder, soda & salt.
Combine butter and egg with oats and buttermilk. Add to processor bowl. Use on-off 5-6 times (Do not overmix).
Spoon into 24 small muffin cups.
Bake 20-25 minutes.