Place cast iron skillet on grill set to medium high heat. Add olive oil and butter.

When butter is melted, add potatoes to skillet. Gently shake pan so that there is one layer of potatoes. Cook on grill until a slight crust forms on potatoes.

Add peas and gently mix into potatoes. Add more butter if vegetables are sticking to skillet.

Sprinkle with salt and pepper. Continue to cook until peas are heated through and still crisp.

Remove from grill. Drizzle with addition olive oil and season to taste.