Peel and finely chop the onion and garlic. Mix with the chickpea flour, parsley, salt, and cumin powder in a container. Slowly add 200 ml of boiling water while stirring. Stir in lemon juice and 1 tablespoon of olive oil. Let steep for 10 minutes. Using wet hands, shape 8 small balls from the dough.
Heat plenty of rapeseed oil in a pan over medium-high heat. Fry the falafel for 8 to 10 minutes until crispy and golden. Let cool for 2 to 3 minutes, then cut each ball in half.
Wash the cucumber, radishes, and mini-peppers. Cut them into thin strips. Wash and finely chop the tomato. Wash the rocket and leave whole or cut in half if preferred.
Put yogurt in a bowl. Season with salt, cumin powder, and lemon juice to taste.
For each tortilla, spread 1 tablespoon of yogurt sauce thinly over the entire surface. Arrange 4 falafel halves on the lower third. Add 3 to 4 pieces each of cucumber, radishes, and mini-peppers, plus roughly 1 finely chopped tomato, and a small handful of rocket.
Fold the ends of the tortilla to the right and left toward the middle, holding them with your index fingers. Roll up from the bottom to the top—the yogurt sauce should hold the edge together. Place seam-side down and cut in half through the middle. Fill, fold, and cut 3 more tortillas the same way.