For the tortillas, mix the flour with salt and parsley in a bowl. Pour in 100 ml (approximately 1/2 cup) of water while stirring, then knead by hand until smooth. Cover and let rest for 15 minutes. Divide the dough into 4 equal portions and roll out on a floured surface to form about 15 cm (approximately 6 inch) diameter circles.
In a nonstick pan, cook the tortillas on each side for about 1 minute. Cook until they develop dark brown spots. Keep warm.
Season the chicken breasts with salt and pepper. Fry in 1 tablespoon of hot oil in a pan on each side for about 5 minutes. Set aside and keep warm.
Rinse the peppers, cut in half, remove the seeds and cut into cubes.
Peel the onion and garlic and chop finely, then fry in remaining oil. Add the peppers and fry for a few minutes and season with salt and pepper.
Blanch the tomatoes in boiling salted water. Peel, remove the seeds and cut into cubes. Set some aside for garnish and add the rest to the peppers and onions and cook briefly.
Peel the avocado, cut in half, remove the pit and cut into slices. Sprinkle with 1 tablespoon lemon juice to prevent browning.
Cut the chicken breast into cubes and mix with the vegetables.
Stir the creme fraiche with 1 tablespoon lemon juice and season with salt and pepper.
Distribute the chicken and vegetable mixture on plates. Drizzle with 1 tablespoon of the creme fraiche and season generously with pepper. Cover with tortillas. Serve garnished with avocado slices and diced tomatoes.