Sift the flour, baking powder, salt and 1/4 cup sugar together into a bowl.
Combine the egg, milk and peanut oil.
Add to flour mixture all at once and stir just until flour is moistened.
Stir in the peanuts.
Fill greased muffin cups 2/3 full.
Bake in 425-degree oven for 15 to 20 minutes or until lightly browned.
Blend remaining sugar and orange rind in a bowl.
Dip hot muffin tops in melted butter, then in sugar mixture.