Wash the potatoes and cook in plenty of boiling water for about 20 minutes. Rinse under cold water, drain and peel. Halve the peppers, clean and wash. Cut the pepper halves into small cubes. Clean the leek, cut in half lengthwise and wash thoroughly. Cut the leek into strips
Cut the potatoes into slices. Heat oil in portions in an ovenproof pan (approx. 24 cm Ø). Fry the potatoes, peppers and leek rings for about 5 minutes in each portion until golden brown. Put all the vegetables back into the pan and season with salt and pepper. Grate cheese finely. Whisk eggs and cream, season with salt and pepper. Pour evenly over the vegetables and sprinkle with Parmesan
Bake the tortilla in a preheated oven (electric cooker: 200 °C/ convection oven: 175 °C/ gas: level 3) for 10-15 minutes until golden brown. Cut the finished tortilla into pieces