Rotisserie Chicken Curry

Ingredients

• 1 tablespoon neutral oil
• 1 yellow onion peeled and sliced into thin wedges
• 1 pound potatoes peeled and cut into bite-sized cubes
• 1 tablespoon butter or ghee
• 2 tablespoons Smoky Tandoor or Golden Curry or both.
• Cayenne powder or crushed red pepper optional, to taste
• 2½ cups leftover rotisserie chicken pulled and diced into bite-sized cubes
• 15 ounces can crushed tomatoes
• 1 cup water or chicken stock plus more if needed
• 15 ounces can coconut milk
• Salt
• pepper
• Cooked basmati rice and sliced scallions for serving