In a large skillet, over medium heat, add one tablespoon of olive oil. Add the sausage and cook for 5 to 6 minutes, until browned and cooked through. Remove the cooked sausage from the skillet and set aside. 

Add remaining 2 tablespoons of olive oil to the skillet and add the sliced bell peppers and onions. Cook for 15 minutes, until tender. 

While the peppers and onion are sautéing cut sausage into bite size pieces. 

Once onion and peppers are tender, add the garlic, diced tomatoes, tomato sauce and tomato paste to the skillet. 

Then add the Italian seasoning, salt, pepper and the sliced cooked sausage. Let simmer for 5 minutes to warm sausage and let everything combine. 

Serve immediately as desired. We love this dish served with pierogis, mashed potatoes, or on a hoagie roll.