Preheat oven (electric cooker: 200 °C/circulating air: 180 °C/gas: see manufacturer). Wash potatoes thoroughly, dab dry, prick several times with a fork and wrap each in a piece of oiled aluminium foil.
Place in the hot oven on the baking rack and bake for about 1 hour. Peel and finely chop the onion. Drain the beans. Heat 1 tablespoon of olive oil in a pot. Fry the onion cubes in it until transparent. Add beans and chunky tomatoes.
Bring to the boil and simmer while stirring for about 5 minutes. Season the sauce with salt, cumin and 1 tsp Tabasco.
Clean the tomato, cut it into quarters and dice it. Halve the avocado and remove the core. Remove the avocado flesh with a tablespoon and cut into cubes. Mix with tomatoes, 2 tablespoons of oil and lime juice.
Wash coriander, shake dry, chop leaves coarsely and stir in. Season with 1⁄2 TL Tabasco and salt.
Wrap the potatoes from the aluminium foil, cut them crosswise and break them open a little. Spread bean sauce, tomato and avocado salsa and sour cream on top.