Peel the onions. Cut the bulbs with a knife from the flower to just before the root (approx. 1.5 cm from the root) 12 times.
Blanch the onions in a wide pot of boiling salted water for 3-4 minutes. Remove and pat dry thoroughly.
Stir 200 ml cold water and 100 g flour until smooth. Season with salt, paprika and cayenne pepper. Dust the onions with flour first (sift over them), then dip them into the dough one after the other (it is best to turn the onion in the dough with your hands!).
Finally, sprinkle each with about 2 tablespoons of breadcrumbs.
Heat the oil in a high pot (to 175 ° degrees). Fry the onions one after the other in hot frying oil for 5-7 minutes until golden brown. Take them out and let them drip off on kitchen paper.
For the dip, peel the garlic, chop it finely and crush it with the flat side of a knife (or crush it in a mortar). Mix mayonnaise and garlic. Season to taste with lemon juice, salt and cayenne pepper.