-pastry shell Saute onions with oil and butter in heavy skillet over low heat until well done, stirring often. Do not brown. Sprinkle with flour and continue cooking slowly about l-2 minutes. Cool well. Beat eegs, add half&half, yogurt, salt, pepper and nutmeg. Add to cooled onions. Sprinkle half the cheese on bottom of prebaked pastry shell and fill with egg-onion mixture. Arrange pepperoni slices on top. Sprinkle with remaining cheese. Bake for 10 minutes at 450, reduce heat to 300 and bake 20 minutes longer.