Preheat your grill on high heat on one half and medium-low on the other. This will ensure a perfect cook for everything.
In a large bowl, combine the onions, bell peppers, olive oil, kosher salt, and black pepper. Toss them together until the vegetables are nicely coated and evenly mixed.
Tear off 4 sheets of Reynolds Wrap® Non-Stick Foil, each measuring about 12 x 18 inches. Lay them flat and ready for filling.
Divide the vegetable mixture evenly among the foil sheets, placing them with the dull side facing up. Top each mound of veggies with about 3 tablespoons of marinara sauce. This will add moisture and flavor as they cook.
Bring up the long sides of the foil to meet over the food. This creates a pocket for steam. Make sure to double fold the ends to keep everything securely inside.
Double fold the two short ends as well, sealing the packets tightly. The idea is to prevent any steam from escaping during cooking.
Place the foil packets on the grill on the side with medium-low heat. Cook until the vegetables become tender, which takes about 25 minutes. You’ll know they are ready when you can easily pierce them with a fork.
Once the veggies are done, set them aside and add the sausage links to the medium-low side of the grill. You can now turn off the high side to save some energy.
Grill the sausage for approximately 6 to 8 minutes, turning often until they are cooked through in the center. This ensures they stay juicy and flavorful.
Once cooked, remove the sausage from the grill and let them rest for a minute on a cutting board. After resting, slice the sausages into bite-sized pieces.
Open the foil packets carefully to avoid steam burns, and add the sliced sausage to each packet. Top each with about 2 tablespoons of mozzarella cheese and leave them open for now.
Cover the grill and let the cheese melt for about 5 minutes. You’ll know it’s ready when it’s bubbly and gooey.
Serve the packets straight from the grill, or let everyone dig in with some crusty bread for a complete meal!
