Scrub the potatoes, leaving the skins on, and cut them into bite-sized pieces.
Toss them with oil, salt and paprika - spread them out on a baking tray lined with baking parchment and roast in a preheated conventional oven (top and bottom heat) at 210°C for about 50 minutes.After about 20 minutes, start on the filling.
Heat a good splash of oil in a frying pan and brown the meat thoroughly. Season with salt and freshly ground black pepper.
Add the onion, peppers, tomatoes, jalapeño and garlic and fry along with the meat for about 10 minutes.
Add the spice mix and tomato purée and heat through for a couple of minutes, then stir in the parsley. Season to taste with salt and pepper - and a little chilli or pickled jalapeños if you want more heat.
Spread the potatoes out in a large ovenproof dish - or on a baking tray you can serve from. Top with the meat and scatter the cheese over.
Don't make the layer too thick, or the potatoes will lose their crispness. Spread it out over a large surface instead for the best result.
Return the dish to the oven for 6-8 minutes at 220°C until the cheese has melted and turned golden - then serve with chopped parsley and ice-cold crème fraîche. A few crushed tortilla chips on top add a lovely crunch.