Braised Chicken Marsala

Name: Braised Chicken Marsala
Ingredients: 4 skin-on, bone-in chicken thighs (about 1 1/4 pounds); 4 chicken drumsticks (about 1 pound); Coarse salt and freshly ground pepper; 1 tablespoon extra-virgin olive oil; 2 red onions, peeled and quartered through the stem; 2 plum tomatoes, cut into 1-inch pieces; 6 sprigs thyme; 3/4 cup Marsala (sweet Italian fortified wine); 1 1/4 cups chicken stock, homemade or low-sodium store-bought; Sage Polenta