Set the oven to 200 °C.
Wash the leeks, but do not remove the outer leaves. At most, cut away the buds, so that you are left with a long stem. Place the leek stalks on the grill of the oven (or on the BBQ) until the outer leaves are blackened and they are soft on the inside. That takes about 30 minutes in the oven and a little less time on the BBQ. Check with a thick needle: if you can easily get through them, they are done. Set them aside and let them cool a little.

In the meantime, make the sauce: put all the ingredients in a chopper, season with salt and pepper and mix. Add a few tablespoons of olive oil until you get the desired consistency.

Take a pair of scissors and cut a strip 3 centimeters wide out of the blackened leek leaves. Cut away the 'roof', so to speak. Remove the soft leeks and cut the stem into pieces of a large centimetre. Put the pieces of leek back nicely and season with fleur de sel and some pepper.

Spoon some of the sauce on each piece. Serve as an appetizer and with a skewer.

Tip: Cooked bell pepper

In Spanish cuisine, cooked peppers are very often used. You can easily find them in the Spanish section of the supermarket. Of course, you can also cook them yourself in the oven.

Tip: Calçots from Catalonia

This is actually a Spanish recipe, where whole onions (which look more like leeks) are placed on the BBQ. But it also works particularly well with regular leeks. The outer leaves char, while the inside becomes particularly soft and sweet, with a hint of smokiness.