First prepare the burger patties. Grind flax seeds finely and mix with 4 tablespoons of water. Roughly chop the onion and garlic. Process them with the remaining ingredients except flour and oil in a food processor or with the help of a blender to a smooth mixture.
Use some flour on your hands to form 4 burger patties and put them on a plate for at least 15 minutes in the fridge to make them a little firmer.
Meanwhile, blend the avocado with the juice of lime to a quick guacamole. Season with salt. Prepare the remaining ingredients: Slice the tomatoes, cut the onions into thin rings and wash the lettuce as well as roughly tear it with your hands.
Fry the burger patties in a large pan with a dash of vegetable oil from one side at medium temperature for about 5 minutes. Turn the burger patties, top each with a slice of cheese and fry for another 5 minutes.
Halve the burger buns and heat in the pan or in the oven. Then just assemble the burger. We do it like that: first a blob of tomato salsa / ketchup, then lettuce and burger patty. Then tomato, onion, jalapeños and tortilla chips. Finally, a dollop of guacamole and then put the lid on it.