1) Preheat oven to 160C/Gas 3.
2) Bring a large pot or water to a boil over medium heat. Add the potatoes and cook until tender, about 12 to 14 minutes. Drain and set aside.
3) In a large oven-proof skillet over medium-high heat, add the butter. Add the onions, peppers and garlic and saute for a few minutes. Add the cayenne pepper, salt, pepper, smoked paprika and oregano. Stir in the chicken and cook for 4 to 5 minutes until chicken is warmed through. Season with more salt and pepper, if needed. Stir in the chicken stock to add some moisture, along with the parsley and lemon juice. Allow to simmer for a few minutes.
4) Add the cooked potatoes and put into the oven until the potatoes are crunchy, about 10 minutes. Remove from the oven and transfer to a serving bowl.