I made up this idea for a bratwurst bath. I have no idea who or what influenced the idea, but I use this technique any time I grill bratwursts. Other than the beer, butter and onions I have no real recipe for this. Bell peppers? Sure! Serrano peppers? Heck yeah! Whatever!
Combine all but the sausages, rolls and mustard in a large saucepan or disposable aluminum pan.
Place over medium heat (I prefer to do this on the grill) and let simmer for at least 30 minutes or until the vegetables start to get tender. You want them to still have a little bite.
Add the sausages and simmer for another 8-10 minutes or until done.
Remove sausages to a grill over medium-high heat. Sear on all sides.