Cook pancetta in a 6-quart Dutch oven over medium heat for 3 to 5 minutes or until pancetta begins to crisp, stirring frequently.

Add olive oil and 2 tablespoons butter; cook and stir until butter is melted. Add onion, carrot, and celery; cook 6 to 8 minutes or until vegetables are tender, stirring frequently.

Add ground beef and sausage; cook over medium-high heat 7 to 9 minutes or until browned (165°), stirring occasionally to break into crumbles. Stir in 1 teaspoon salt, nutmeg, and black pepper.

Remove Dutch oven from heat. Stir in wine; return to heat. Cook over medium-low heat, scraping brown bits from bottom of Dutch oven. Simmer 5 to 7 minutes or until reduced by half. Stir in tomato paste. Add undrained tomatoes and 2 cups chicken broth. Simmer, uncovered, over low heat 4 to 5 hours or until desired consistency, stirring occasionally.

For polenta, bring remaining chicken broth and ¼ teaspoon salt and garlic cloves to a boil in a large saucepan. Add 2 cups half and half; stir in grits or polenta. Simmer, uncovered, over low heat 25 to 30 minutes or until desired consistency, stirring occasionally. Remove and discard garlic cloves. Stir in remaining 8 tablespoons butter and 2 cups Parmigiano Reggiano until melted. Remove from heat; let stand, covered, 3 minutes.

To serve, stir remaining ½ cup half and half into tomato sauce mixture; serve over polenta. Garnish with additional cheese and basil, if desired.