Preheat oven to 425 degrees. Line a sheet pan with aluminum foil or parchment paper and coat lightly with cooking spray.
Toss Italian Sausage and veggies in oil, salt and pepper. This can be done in a separate bowl or on the sheet pan itself. Mix until evenly coated.
Spread out sausage and veggies evenly on sheet pan. Bake for 15-20 minutes, flipping sausage and veggies over halfway through, until sausage is fully cooked and veggies are soft. Optional: Serve roasted sausage and veggie mix over pasta, with parmesan sprinkled atop.
Put your sausages in the freezer like 15-20 mins before you're ready to cook. It will be MUCH easier to cut them when they're firmer.
Slice meat into quarter-sized pieces to ensure it cooks quickly.
Sausages are fully cooked when no longer pink, the juices from the meat run off clear, and the internal temperature reaches 160ºF.
Control grease. If serving sausage and veggies over pasta, keep in mind that baked Italian sausage generates some excess oil, which can help flavor the pasta. But if it's too much grease for you, you can scoop your sausage/veggies onto a paper towel before topping on pasta.
Store baked sausage and veggies covered in the fridge for 3-4 days. Or you can freeze leftovers in an airtight container for up to 3 months.