Heat the oven to 325 F.
In a large oven safe skillet (cast iron) brown the sausage over medium heat.
Meanwhile, whisk the eggstogether in a medium bowl. Add salt and pepper. Set aside.
After the sausage is about half done, add in the diced onion, pepper and asparagus. Cook until the sausage is done and onions and peppers start to get tender, about 7 minutes.
Add the eggs to the skillet and incorporate with the meat and vegetables.
Transfer the skillet to the oven and cook for 25 minutes, or until the eggs no longer jiggle.