Scrub potatoes and dry with paper towels.
Cut the potatoes in half and score the insides in a criss cross pattern with a sharp knife about 1/2 inch deep.
Brush the potatoes with olive oil and season with salt and pepper.
Press the potato halves back together.
Make a foil packet for the potatoes, sealing completely.
Cook the potatoes over indirect fire with the grill closed for a total of 1 hour 15 minutes to 1 hour 30 minutes, until potatoes yield when squeezed and are cooked through.
For the Chicken
To spatchcock the chicken, cut down one side of the backbone and flatten with your hands.
Pat chickens dry with paper towels and place on a rimmed baking sheet.
Mix butter, garlic, smoked paprika, salt and pepper together in a bowl.
Carefully loosen the skin and spoon butter mixture between the skin and meat, rubbing it all over.
Cook the chicken, cut side down for about 1 hour to 1 hour 15 minutes, cooking until chicken reaches 165° using a digital meat thermometer to check in the thick part of the thigh.
For the Skillet
Remove chicken to a clean baking sheet and cool slightly.
Potatoes can be removed from the foil packet.
Dice the onions and bell peppers and sauté in olive oil over medium heat until vegetables are softened.
Shred the chicken.
Arrange potato halves in a cast iron skillet. Make a diagonal cut across the potatoes but not all the way through and smash the potatoes flat.
Top potatoes with half of the cheese.
Add the sautéed vegetables and shredded chicken.
Top with remaining cheese.
Sprinkle with diced tomatoes.
Place the skillet on the grill and cook about 5- 8 minutes with the grill closed until cheese is melted.
Garnish with parsley or cilantro if desired.
Serve with sour cream.