Recipe - Polenta With Roasted Fennel Sauce

1 md Fennel bulb
Cut into 1/2inch pieces
One half cup Coarsely minced onion
2 Cloves garlic; cut or sliced up thin
1 One half teaspoon Olive oil
Cooking spray or oil
24 ounce Roll prepared nonfat polenta
14 ounce Crushed tomatoes
1 teaspoon Red pepper flakes; or to
taste
2 tablespoon Grated Parmesan cheese;
(optional)
1 tablespoon Finely chopped fennel fronds

Makes 4