In the crockpot, add in the sliced bell peppers, onions, seasonings and marinara sauce. Mix them around the best you can. They will be raw, so they won’t bend.
Add the entire Italian sausage links into the crockpot, do not chop them.
Cook on high for 4 hours, allowing all the veggies to soften. Taste before serving you may want a little more salt.
Lastly, once done cooking, serve on a bun and for extra flavor a bit of mozzarella cheese.