In a large pan over medium high heat, add olive oil. Once
hot, add chicken skin side down. Cook for 7-10 minutes, not moving the chicken around, allowing the skin to crisp up. Turn chicken over, continue cooking for 5 minutes more.
Place half of the tomatoes, onions, mushrooms, garlic, herbs, red pepper flakes, sugar, and red wine in the crockpot. Add chicken thighs then top with remaining ingredients. Cover and cook on low for 6 hours. Remove lid during last hour to let sauce thicken up.
Serve with spaghetti and top with parmigiano reggiano.