Begin by washing and slicing your russet potatoes into ¼-inch rounds for even cooking. Cook the bacon until crispy, then crumble it into small pieces. Next, thinly slice the onion and shred the cheddar cheese, setting them aside.

Cut four sheets of heavy-duty aluminum foil, roughly 12x12 inches each. On each sheet, layer the sliced potatoes, crumbled bacon, shredded cheese, and sliced onions. Season each layer with salt, pepper, and garlic powder.

Place a small pat of butter on top of each layered mixture, followed by a drizzle of heavy cream or milk.

Fold each sheet of foil carefully to create a tightly sealed packet, ensuring that no steam can escape during cooking.

Place the sealed packets directly over hot coals or on a grill preheated to medium. If using an oven, set it to 400°F (200°C). Cook the packets for 30-45 minutes, turning them every 10 minutes.

After 30 minutes, carefully open one packet using heat-resistant gloves. Pierce the potatoes with a fork; they should be tender.

Once fully cooked, open the packets carefully to release the steam and enjoy the aroma. Serve directly from the foil.