Cook pasta. See the package instructions for cooking time. Drain and set aside.
Heat large pan over medium-high heat. Toss in sausages and let them brown on both sides.
Add butter, onions and bell peppers. Stir until butter has melted.
Add pasta. Sprinkle a pinch or two of salt and ground black pepper. Don't mix. Cover and reduce heat to medium. Cook for 25 minutes.
Remove cover and mix well. It should be done.
Serve hot or warm.