Heat a large skillet over medium heat with a tablespoon of olive oil. Place the sausage in the pan and brown on both sides, moving and turning around in the pan regularly, so it browns evenly for about 2-4 minutes.
Gently pour about ⅓ cup water (you can use the pasta water) into the skillet to prevent the sausage from burning or sticking to the pan. Cook for about 8-10 minutes or until it’s almost cooked. The sausage will finish cooking with the pasta.
Remove the sausage from the pan, put it on a cutting board, and slice it into desired-sized pieces. Set aside.
Drain all excess liquid from the frypan, making sure it is completely dry.
Add butter, followed by onions, thyme, Creole seasoning, Italian seasoning, and chili flakes. Sauté for about 2-3 minutes.
Add garlic and tomato paste, continue cooking for another 2-3 minutes, stirring constantly.
Throw in the diced tomatoes and continue cooking. Add a tiny bit of water if the pan gets is too dry. Continue cooking for another 2-3 minutes.
Return the sausage together with any accumulated juice back to the skillet, followed by bell pepper.
Stir in the broth and cook for about 5-7 minutes, or until the sausage is cooked through and sauce thickens. Lightly season with salt and pepper.