Adjust ingredients according to taste (more sausage, less peppers, extra cheese, etc)
Slice peppers and onions; Cook with sausage as desired (I did this all on my grill).
About 3/4 through the cooking time, liberally butter brioche, place on grill to toast; remove when toasted to desired doneness.
Begin assembly; bread, one slice havarti, sausage and peppers, one slice gouda, bread.
Simple and delish.