Prep the bacon and veggies. Cook bacon until crisp, then crumble and set aside. Halve baby potatoes, chop broccoli, bell pepper, and onion.
Preheat the oven to 425°F (220°C) or heat the grill to medium-high.
Par-cook the potatoes (recommended). Toss potatoes with 1 tablespoon olive oil, salt, and pepper. Microwave covered for 3–4 minutes or boil for 5 minutes to soften slightly. This helps them finish at the same time as the chicken.
Season the chicken. In a bowl, mix chicken pieces with ranch dressing, dry ranch seasoning (if using), garlic powder, smoked paprika, 1 tablespoon olive oil (or bacon fat), and a pinch of salt and pepper.
Stir to coat well.
Build the foil packets. Lay out four sheets of heavy-duty foil. Divide potatoes among the sheets, then top with chicken, broccoli, bell pepper, and onion. Sprinkle evenly with crumbled bacon, reserving a little for garnish if you like.
Seal tightly. Fold the long sides of the foil up and over the filling, then crimp to seal.
Fold and crimp the ends to create a tight packet. Make sure there are no gaps so the steam stays inside.
Cook. Oven: Place packets on a baking sheet and bake for 20–25 minutes, until chicken is cooked through (165°F/74°C) and potatoes are tender.
Grill: Place packets seam-side up on the grill. Cook for 18–22 minutes, flipping once halfway through if your grill has hot spots.
Add the cheese. Carefully open packets (watch the steam). Sprinkle with shredded cheddar, then re-seal loosely and cook for 2–4 minutes more, just until the cheese melts.
Finish and serve. Open packets, garnish with fresh parsley or chives, and a drizzle of extra ranch if desired.
Serve hot, straight from the foil or transfer to plates.