Mix garlic powder, onion powder, salt, and pepper over each sausage.
Cut each bell pepper in half vertically. Cut off stems and remove seeds.
Slice the red onion into thick round slices.
Using the basket supplied with the rotisserie, arrange the sausages, peppers, and onions evenly.
Place basket into the rotisserie and set the timer for 25 minutes, Cook until internal temperature reaches 160° F (71.1° C)