cook the potatoes
In a large pot filled with salted water cook the potatoes, leaving the skin on. Cook for about 40 minutes, or until just cooked. Peel the potatoes and chop them into small chunks. Peel the onions and thinly slice them.
Fry the onions
Set a skillet over a medium high heat. Add the olive oil, onion slices, anchovy fillets, pinch of sea salt and pinch of black pepper. Fry for about 10 minutes, stir occasionally.
Add the baby spinach, cooked potatoes and a pinch of ground nutmeg. Stir well and arrange all over the skillet. Fry for about 2 minutes.
In a small bowl combine the eggs, one teaspoon of sea salt, two pinches of black pepper, pinch of cayenne pepper, pinch of smoked paprika and tabasco sauce. Add grated parmesan and sour cream, stir well. Pour this mixture over the tortilla, cover with a lid, lower the heat and bake for about 25 minutes. Toss the skillet occasionally.
Serve tortilla the patatas with baby spinach, a generous dollop of greek yogurt or sour cream / crème fraîche.