In a nonstick pan heat the oil and butter on medium high heat. Season chicken with a pinch of salt and pepper and coat with flour. Brown chicken in the pan for 3 minutes per side, just until browned. Remove from pan and set aside.
Add onions, peppers, and mushrooms to the pan and cook until softened, about 7 to 10 minutes, stirring occasionally. Add in tomato paste, garlic, Italian seasoning, and cook 1 to 2 minutes more.
Pour in the wine and crushed tomatoes and stir to combine.
Return the chicken to the pan and let simmer until chicken is cooked through to an internal temperature of 160 degrees Fahrenheit, about 15 minutes.