Wash the potatoes and cook in boiling water for about 20 minutes. Then rinse with cold water, peel and leave to rest for a while. In the meantime soak toast in cold water. Peel, wash and thinly slice the carrots.
Knead minced meat, toast, mustard and tomato paste and season with salt, pepper and paprika. Make a small meatball from the minced meat mixture and chill. Cut the potatoes into slices. Heat 1 tablespoon of oil in a pan (approx. 24 cm Ø).
Sauté half of the potatoes for about 3 minutes. Wash the marjoram, dab dry and chop the leaves finely, except for 2 stalks. Add half of the carrots and peas and season with salt and pepper.
Whisk eggs, marjoram and milk, season with salt and pepper. Pour evenly over potatoes and vegetables. Allow to set at reduced heat for 10-15 minutes. (Close the pan with a lid if possible.) Heat 3 tablespoons of oil in a pan.
Fry the meatballs in portions at medium heat for 8-10 minutes. Carefully turn the tortilla onto a plate (ovenproof) and cook in the preheated oven (electric cooker: 175 °C/ convection oven: 150 °C/ gas: level 2) for another 4-6 minutes.
Heat 1 tablespoon of oil in a frying pan and prepare another tortilla in the same way. Arrange the tortilla and meatballs on a plate or platter and garnish with marjoram.