Mix cornstarch, flour and seasonings until well blended. Add beer, mix well. Cut about 3/4" off top of onion and peel. Cut into onion 12 to 16 vertical wedges but do not cut through bottom root end. Remove about 1" of petals from center of onion. Dip onion in sesoned flour and remove excess by shaking. Separate petals to coat thoroughly with batter. Gently place in fryer basket and deep-fry at 375 to 400~ 1-1/2 minutes. Turn over and fry 1-1/2 minutes longer or until golden brown. Drain on paper towels. Place onion upright in shallow bowl and remove center core with circular cutter or apple corer. Serve hot with Creamy Chili Sauce. Seasoned Flour- Combine flour, paprika, garlic powder, pepper and cayenne and mix well. Creamy Chili Sauce-Combine mayo, sour cream, chili sauce and cayenne and mix well.