The Recipe: Mackerel, Rhubarb, Bay Leaf
Compliments of A Very Serious Cookbook by Contra Wildair (Phaidon)
We use fruit a lot in savory applications, especially if it’s in season and not being used for desserts. It’s sweet, yeah, but really I like fruit in savory applications for its acidity, and rhubarb is king of the acidic fruit. The kind of rhubarb we get in New York is rarely that deep ruby color but mostly pretty green. It gets its insane acidity from oxalic acid (sorrel and rhubarb both have this, which explains why they both have that same unique tanginess), making the juice super potent. Aside from juicing it raw, we also gently cook it to make a tea, which still has plenty of brightness, but with a touch of sweetness for better balance.
Even though the fish is sort of cooked in this dish, there’s so much fresh, acidic liquid that it’s almost like eating a ceviche. Spanish mackerel is much thicker and meatier than Boston mackerel, which makes it heartier but also easier to cut with a spoon when eating in something like a broth.
For the Rhubarb Broth
Fresh lemon juice
For the Mackerel and Assembly
8 Spanish mackerel fillets
200g olive oil, plus more for the spring onions
100g canola (rapeseed) oil
50g unsalted butter, at room temp.
200g kohlrabi, peeled
Fresh lemon juice
160g small, thin, wild spring onions
Bay Leaf Oil
1.2kg neutral oil
180g fresh bay (or wild bay) leaves
1 Peel the rhubarb and trim the ends. Combine the water, rhubarb peels and scraps, and sugar in a heatproof medium bowl and cover it tightly with plastic wrap (cling film).
2 Set the bowlover a pot of simmering water for about 1 hour. This will encourage the rhubarb to sweat out its juices and infuse the water. Strain this “rhubarb tea” into a bowl and let cool.
3 Run the peeled rhubarb stalks through a juicer. Combine the rhubarb juice with the rhubarb tea. Add the umeboshi and season with salt
Bay Leaf Oil
Heat the oil in a medium pot to 180°F (82°C). Add the bay leaves and remove from the heat. Let cool completely. Once the oil is cold, transfer to a blender and puree until smooth. Strain through a fine-mesh sieve lined with cheesecloth. Cover and refrigerate.
Mackerel & Assembly
1 Place the mackerel skin side down on a work surface and slice each mackerel fillet into thirds but do not cut through the skin.
2 Preheat the oven to 300°F (150°C/ Gas Mark 2. Heat the 200 grams of olive oil and the canola (rapeseed) oil in a large, wide pot over medium-low heat to 132°F (56°C).
3 Let the mackerel sit at room temperature for 10 minutes before adding to the oil. Cook, undisturbed, until fish is about 50 percent cooked (it should be white around the edges, but still rather opaque in the center.
4 Using a fish spatula, lift the mackerel fillets out of the oil and onto a sheet pan, skin side up. Place in the oven for 2 minutes just to finish cooking.
5 Remove from the oven and brush the skins with the softened butter. Using a kitchen torch or Searzall, torch the skin of the mackerel until it’s browned, bubbling, and lightly crisped.
6 Slice the kohlrabi into slabs about ¼ inch (1.25 cm) thick, then into sticks ¼ inch (1.25 cm) wide. Cut them into matchsticks 2 inches (5 cm) long. Place in a medium bowl and season with lemon juice and salt. Cut the spring onions into 2-inch (5 cm) pieces (they should be the same size as the kohlrabi).
7 Heat a medium cast-iron skillet over high heat. Once the pan is very hot add the spring onions and cook, tossing to get them wilted and evenly charred, 2–3 minutes. Remove from the heat and toss with olive oil and season with salt.
8 To plate, place 6 pieces of mackerel in each dish and ladle about ¼ cup of rhubarb broth over. Top with the kohlrabi and spring onions and drizzle with the bay leaf oil.