Pre-heat oven to 350F/180C.
Peel and dice the potatoes into very small chunks approx 1/2" x 1/2" (1.3cm x 1.3cm)
Add the chorizo to a 12" oven-safe pan over low-medium heat. Fry until the fat begins to leak out and the chorizo crisps up a little on each side. Remove from the pan and leave the fat behind.
Season the chicken all over with 1/2 tsp salt and 1/4 tsp black pepper. Raise heat to medium-high and place the chicken into the pan. Fry both sides until the chicken turns golden and begins to form a crust. Don't worry too much about it cooking right through at this point. Remove from the pan, leaving the fat behind.
Lower heat slightly to medium and add in the onion, red pepper and garlic. Fry until it all begins to soften, then add the sun dried tomatoes alongside the chicken and chorizo. Pour in the tomatoes and swill out the cans with a splash of water (couple tbsp each can). Add in 1 tsp smoked paprika, alongside 1/4 tsp salt & sugar and 1/8 tsp (or to taste). Give it all a good stir then cut the heat.
Cover the top with the potatoes in an even layer, closing as many of the gaps as possible. Generously season the top with salt & pepper, then give it a good spray all over with oil.
Place in the oven for 35mins, then take it out and scatter over the feta & oregano. Gently push down any potatoes that are starting to char too quickly. Place back in the oven for 10mins until the potatoes are crispy on top and completely soft all the way through. The sauce underneath should have reduced so it's no longer watery.
Serve up and enjoy!