Once it comes to temperature, place the bratwurst directly on the grilling grates for 45 minutes, rotating them throughout the cooking time.
While the bratwurst is cooking, prepare a sheet of foil with olive oil or grapeseed oil cooking spray.
Slice the bell peppers and onion and place on the sheet of foil.
Wrap up the vegetables and place them on the grill alongside the bratwurst, these can cook for about 30-45 minutes.
After 45 minutes, up the temperature on the pellet grill to 375°F and continue cooking the bratwurst for 5-10 minutes to crisp up the outside of the bratwurst.
Remove the vegetables and prepare a bun along with the bratwurst, then top with vegetables and condiments of your choice.
Notes
The internal temperature needs to be at least 165°F to be considered done.