01 - In a large bowl, toss sliced bell peppers and onion with olive oil, salt, and black pepper until evenly coated.
02 - Preheat the grill to medium heat. Place Italian sausage links on the grill and cook for 15 to 20 minutes, turning frequently to ensure even browning and an internal temperature of 160°F.
03 - Arrange the coated peppers and onions in a grill basket or directly on the grill. Cook, stirring occasionally, until vegetables are softened and slightly charred, about 10 to 12 minutes.
04 - Transfer grilled sausages and vegetables to a serving platter. Serve immediately while hot.