Preheat your oven to 400°F (200°C). Slice the sausage into bite-sized rounds, and wash and slice the bell peppers and onion into thin strips.

In a mixing bowl, combine olive oil, minced garlic, Italian seasoning, salt, and pepper, and stir until well combined.

Transfer the sliced sausage, bell peppers, and onion onto a baking sheet. Drizzle the seasoned olive oil mixture over the ingredients and toss to coat.

Spread the mixture into an even layer on the baking sheet and bake for 35-40 minutes, stirring halfway through.

Remove from the oven and let cool for a few minutes before serving. Garnish with fresh parsley or a squeeze of lemon.