01 -
Attach two bay leaves to a small onion using four cloves.
02 -
Finely chop the leeks and sauté them in 2 tablespoons of olive oil over medium heat until soft, avoiding browning.
03 -
Place the milk in a pot, add the prepared onion, and heat to 175˚F (80˚C).
04 -
In a medium pot, melt the butter, then add flour. Stir briskly and cook to eliminate the raw flour taste.
05 -
Gradually add the hot milk, removing the onion first. Stir quickly to incorporate all the milk until smooth.
06 -
Add sea salt and ground nutmeg. Cook while stirring until the béchamel thickens and holds its form when pulled away from the sides of the pot.
07 -
Add the sautéed leeks to the béchamel and stir until evenly combined.
08 -
Transfer the mixture to a container, cover with parchment paper, and refrigerate overnight.
09 -
Form the chilled mixture into 50 g (1.75 oz) round balls. Dip each croquette in beaten egg with milk, then coat in breadcrumbs. Store in a container until ready to fry.
10 -
Heat olive oil to 320˚F (160˚C). Fry the croquettes until golden brown and cooked through. Drain well on a paper towel-lined plate or tray.
11 -
Serve hot with mayonnaise, if desired.