Sourdough Corn Bread

1 cup sourdough
1/3 cup oil or butter
1 egg
1/2 cup all-purpose flour
3/4 teaspoon baking soda
1/4 cup salt
1 cup cornmeal

Mix sourdough, egg and oil. Sift together dry ingredients. Add to sourdough mixture. Mix until well blended. Pour into an 8-inch square pan. Bake at 350 degrees F for 25 to 30 minutes.