1 large unpeeled sweet onion (or red onion), cut lengthwise through stem and root ends into quarters
4 or 5 medium-sized Roma-style tomatoes, cored and cut in half lengthwise
8 to 10 medium-sized, fresh mushrooms
1 sweet bell pepper, pierced in 2 places with a knife
2 Anaheim chilies, pierced in 2 places with a knife
4 cloves garlic, unpeeled (snip off tips, and then secure all 4 cloves on a bamboo skewer)
Extra-virgin olive oil, as needed
Roasted polenta squares (see related recipe)
Freshly grated Parmesan cheese, for serving
Brush the onions, tomatoes and mushrooms with the olive oil and then place all vegetables (including skewer of garlic cloves) on a grill 4 to 6 inches above a bed of medium coals or gas flame. Onions should be placed with cut-sides down; tomatoes should be placed cut-sides up. Turn all vegetables except tomatoes as they brown. As tomatoes brown on bottoms and become very soft, remove to a bowl.
Continue cooking onions, turning often, until they are tender, about 10 to 12 minutes. The bell peppers and chilies need to be turned several times so they will brown evenly on all sides.
Remove browned vegetables and store in bowl with tomatoes, refrigerated for up to 24 hours, or proceed with recipe.
Cut each onion quarter into thin slices. Dice tomatoes and mushrooms. Peel and cut peppers into pieces. Mince garlic cloves. Return vegetables to bowl and set aside. Drizzle with additional olive oil and season with salt and pepper to taste.
To serve, remove the roasted polenta from oven and place 1 to 2 pieces on each plate. Top polenta with a serving of grilled vegetables. Pass additional Parmesan at the table.
Makes 4 servings.