Onions peel and in fine cubes cut. Wash and halve the chilli, remove the seeds. Chop the pod finely. Mix 2 tablespoons lemon juice, salt, sugar and olive oil. Mix oil mixture with onions and chili. Chop the oregano, except for a little bit for garnishing, and stir into the onions
Cut the avocados in half, remove the seeds and peel the flesh. Cut the flesh into thin slices and sprinkle with some lemon juice
Season sour cream with salt and cayenne pepper. Spread on 4 tortillas, cover each with 1/2 avocado and sprinkle each with 3 tbsp. cheese. Cover with the remaining tortillas and press on. Fry the quesadillas one after the other for about 2 minutes on each side in a pan greased with oil. Cut the quesadillas into cake pieces. Arrange salsa and quesadillas and garnish with oregano