Heat 1 tablespoon of olive oil in a large skillet over medium heat until shimmering.

Add the sliced andouille sausage rounds to the hot oil and cook for about 5 to 6 minutes, turning occasionally, until browned on all sides. Remove the sausage from the skillet and set aside.

Increase the heat to medium-high, add the remaining 1 tablespoon of olive oil to the skillet, then add the red and yellow bell peppers along with the sliced onion. Sprinkle the Italian seasoning over the veggies and cook for 4 to 5 minutes, stirring occasionally, until the vegetables are crisp-tender.

Stir in the minced garlic and season with salt and freshly ground black pepper to taste. Continue cooking for another 1 minute to allow the garlic to release its aroma but not burn.

Return the cooked sausage to the skillet, mixing it with the vegetables. Cook everything together for 1 more minute until the sausage is heated through.

Taste the dish and adjust salt and pepper if needed. Garnish with optional red pepper flakes, sliced green onions, and fresh chopped parsley or basil.

Serve the sausage and peppers skillet on its own or over rice or noodles as desired.