Warm the olive oil in a large skillet over medium heat. (Choose a skillet with a lid if you have one.) Add the sausage links, whole, and cook for 2-3 minutes, turning frequently. Remove when they are browned on the outside; they don't need to be quite fully cooked through. Set aside to cool slightly, then slice into pieces 1 to 2 inches in length.
1 Tablespoon olive oil, 18-20 ounces Italian sausage links
In the same skillet, melt the butter, then add sliced onions and peppers. Cook for 1-2 minutes.
1 Tablespoon butter, 1 large onion, 2-3 bell peppers
Stir in the garlic and cook for 30-60 seconds more, just until fragrant.
4 cloves garlic
Stir in the chicken broth, diced tomatoes with all juices from the can, Italian seasoning, salt, and pepper. Scrape the bottom of the skillet to release any browned bits, then let the sauce come to a simmer.
1/4 cup low-sodium chicken broth, 1 (15 ounce) can diced tomatoes, 1 teaspoon Italian seasoning, 1/2 teaspoon kosher salt, 6-8 cranks freshly-ground black pepper
Once the liquid is bubbling, return sliced sausages to the pan, cover, and cook for about 5 minutes. Reduce the heat if needed; ideally the simmer stays gentle, not too vigorous.
Uncover and cook 2-3 minutes more, until the sauce is slightly reduced and the sausage is cooked through. Season with more salt and pepper to taste. Garnish with chopped fresh herbs, if desired, and serve right away over pasta, mashed potatoes, veggies, with bread, etc.
fresh parsley and basil