Warm the olive oil in a large skillet over medium heat. Add the sausage links and cook for 2-3 minutes, turning frequently. Remove when they are browned on the outside, but not yet cooked through. Set aside to cool slightly, then slice the links into 1-2” pieces.

In the same skillet, melt the butter, then add sliced onions and peppers. Cook for 1-2 minutes, then add garlic and cook for 30-60 seconds more, just until fragrant. Stir in the chicken broth, diced tomatoes, Italian seasoning, salt, and pepper, scraping the bottom of the skillet to release any browned bits.

Bring everything to a simmer, then return the sliced sausages to the pan. Cover and cook about 5 minutes, reducing the heat if needed - the bubbling shouldn’t be too vigorous. Uncover and cook 2-3 minutes more, until the liquid is slightly reduced and the sausage is cooked through. Garnish with chopped fresh parsley and basil, if desired, and serve right away.