Preheat the oven to 200 ºC. Peel and cut the sweet potato in cubes. Drain the beans and cut the beets into cubes as well. Cut the red onion into rings and drizzle with lime juice from half a lime.
Fry the sweet potato in some oil for about 10 minutes while stirring. Rinse the beet pieces and fry them briefly with the sweet potato. Fry the kidney beans and sprinkle everything with Mexican spices while baking.
Fry the marinated pieces in another frying pan according to the instructions on the package. Heat the tortillas in the oven.
In order to make guacamole (optional), mash 2 ripe avocados and mix with a generous tbsp of crème fraîche, 1 finely chopped tomato (pulp without seeds), 1 finely chopped garlic clove and season with salt, pepper, generous lime juice and coarsely chopped fresh coriander.
Spread some guacamole on top and top with some spinach. Divide the baked sweet potato with beet on top and the marinated pieces. Garnish with jalapeno pepper, pickled red onion and cilantro (optional).