Jill's Famous Oatmeal Muffins

(I always get lots of compliments when I make these. )
1 egg
1/2 cup brown sugar
1 cup buttermilk
1/3 cup shortening
1 cup quick cooking oats
1 cup flour
1/2 tsp. baking soda
1 tsp. salt
1 tsp. baking powder

Preheat oven to 400 degrees. Grease 12 medium muffin cups.
In a large bowl, beat egg. Stir in buttermilk, brown sugar and shortening. Mix in remaining ingredients until flour is just moistened. Batter should be lumpy. (I use my hand mixer.)
Fill muffin cups 2/3 full with batter. Bake at 20-25 minutes or until golden brown. Immediately remove from pan and cool on wire racks.