Potato crusted Branzino is a spectacular dish and yet, doable. It is inspired by Paul Bocuse's iconic recipe ''Le rouget en écailles de pommes de terre''. Rouget (red mullet) can be subbed for Branzino/Loup de Mer (“the wolf of the sea”). It has very mild flavor. It's also a very easy fish for customer to eat off the bone or to fillet themselves. Otherwise, ask your fishmonger to descale and filet fish.
This dish is served with beurre blanc/beurre Nantais and fried leeks.
Purchased fresh fish should not be kept in their original packaging. Arrange fish over a frozen baking tray lined with parchment and cover with plastic film. Keep fish in the refrigerator with ice packs underneath or a bag of ice on top – Store for up to 48 hours.
Clarified butter can be made long in advance. To make clarified butter, place butter in a saucepan over gentle heat, do not stir the butter while it is melting. Turn the heat off. Or, microwave it for a min or so (covered). Let it sit for 15 minutes or so until milk solids ''petit lait'' have sunk to the bottom. Carefully pour butter fat to another container; discard liquid. Or, place melted butter in the refrigerator until fat solidifies, which takes a few hours. Take the chilled butter fat out and discard milk solids. As the milk solids have been removed, ghee doesn't go rancid as rapidly as ordinary butter does, so refrigeration is not so essential. However, it will extend its life.
Melt clarified butter and mix with corn starch. Butter-starch mixture can be made in advance and kept refrigerated for awhile – slightly rewarm prior to use.
To get perfectly calibrated potato scales, use a quarter dollar as a guide. With a mandoline, cut potatoes into 2 mm thick slices and cut into an inch/2.5 cm diameter rounds (protect your hand using a cut-resistant glove). Save scraps and soak them in water for up to 3 days. Renew water each day. Drain, pat dry and fry!.
Place potato scales in a saucepan, cover with tap water – bring to a light boil and turn the heat off. Skim off foam and drain. Spread hot potato scales over a tray lined with paper towels.
First brush fish filet with butter-starch mixture and toss potatoes in butter mixture. Arrange the potato slices over the filet (starting with 4 from the top) in overlapping rows so that they look like fish scales. Repeat with remaining filets and refrigerate for up to 24 hours.
Cut top and bottom leek. Divide into 4.5-inch/12cm logs and cut into thin julienne. Soak in lukewarm water. Drain and pat dry and fry. Transfer to a bowl lined with paper towel. Season with salt and pepper while still hot; set aside.
Fry potato scraps just like French fries. It works beautifully!
Beurre Blanc (white butter) is a classic butter sauce that is both creamy and tangy—perfect for drizzling over fish, poached eggs, or vegetables. The original recipe does not contain any cream. Though, cream is often added as a stabilizer to the sauce. In a small saucepan add wine, vinegar, shallots, herbs and peppercorns. Cook until the liquid is almost completely reduced. Add heavy cream, bring to the boil and reduce by two-third. Pass through a sieve and put creamy mixture back to the saucepan. Throw in the pieces of butter, a few at a time, whisking constantly over low heat. Season with salt and white pepper. Beurre blanc must not boil or it will separate. If it happens, use a separate saucepan and reduce 70g heavy cream to two-third. Set heat to low and pour back beurre blanc sauce on thin stream whisking rapidly. Keep sauce warm until ready to serve or quickly rewarm over the stove prior to serve.
Heat up skillet on medium high heat and add a tablespoon clarified butter. Season potato scales with salt. Cook fish potato side down – season flesh with salt and pepper. Cook for about 12 mins or until the flesh turns almost completely opaque. Lower the heat and throw a tablespoon of butter, fresh thyme or rosemary and a couple of crushed garlic cloves. Baste fish with it – turn off the heat and flip the fish and baste again.
Remove fish and lay over paper towels for 20 sec prior to plate.
In the center of each plate, add some warm beurre blanc and place the hot potato crusted branzino. Garnish with some fried leeks and lemon wedge coated in chopped parsley.