1. Let butter stand until room temperature. (Butter should be very soft.)
2. Cut off pointed end of garlic; place garlic on a piece of aluminum foil, and drizzle with oil. Fold foil to seal.
3. Bake at 400° for 1 hour; cool. Squeeze pulp from garlic cloves. Combine 1 1/2 tsp. pulp and butter in a medium bowl, reserving remaining garlic for another use. Stir in peppers and basil. Brush on hot grilled corn, and sprinkle evenly with Parmesan cheese.