Pat chicken pieces dry and season with salt and pepper.
Heat 2 Tablespoons olive oil and 1 Tablespoon butter in a large heavy straight sided sauté pan over medium-high heat until it shimmers. Add chicken pieces in small batches and cook until browned on all sides. Set chicken aside and cover with foil until all chicken is done.
Remove all but 2 Tablespoons of fat.
Return chicken to pan and add Cacciatore Simmering Sauce. Reduce heat and simmer covered for 30 minutes. Remove lid and simmer an additional 15 minutes.
Follow above instructions through step #2. Place sautéed chicken pieces and sauce in a slow cooker, stir and cover. Cook on high for 2 1/2 hours or low for 4 hours. Add 1/4-1/2 cup water, wine or chicken stock if sauce gets too thick.