Smear the mayo over these cakes and encourage your guests to dunk them in the stew. Make them up to one hour ahead, and keep warm on low in the oven.
Stir together first 3 ingredients in a small bowl.
Stir together buttermilk, egg, and 2 Tbsp. oil. Stir into cornmeal mixture just until blended. Stir in green onion.
Brush 1 Tbsp. oil on a hot griddle. Drop cornmeal mixture by 1/8 cupfuls onto hot griddle. Flatten to 1/2 inch thick, and cook 1 1/2 to 2 minutes on each side or until golden. Repeat process with remaining batter and oil.