Roasted Lion's Mane Mushroom Recipe

Preheat and prep

Preheat oven to 425°F (220°C). Clean the lion's mane mushroom by brushing gently with a pastry brush or a damp cloth to remove debris. Tear or slice the mushroom into 1/2–3/4-inch thick pieces or pull into large chunks to expose the 'teeth'—this creates more surface area for browning.

Season

In a bowl, combine 2 tbs extra-virgin olive oil, 1 tbs melted unsalted butter, minced garlic (use a garlic press or finely mince), 1 tsp fresh thyme leaves, 1 tsp kosher salt, and 1 tsp freshly ground black pepper. Add the mushroom pieces and toss gently to coat evenly.

Roast

Arrange the mushrooms in a single layer on a rimmed baking sheet lined with parchment or a lightly oiled sheet. Roast for 18–22 minutes, turning once halfway through, until edges are golden brown and crisp and centers are tender. If pieces are large, roast up to 25 minutes.

Finish

Remove from oven and squeeze the juice of half a lemon over the mushrooms. Taste and adjust seasoning with a little more salt or pepper if needed. Keep warm while you make the béarnaise.

Make tarragon reduction

In a small saucepan, combine 2 tbs white wine vinegar, 2 tbs dry white wine, and the minced shallot. Add 1 tbs of the chopped tarragon leaves. Bring to a simmer over medium heat and reduce until about 1 tablespoon of liquid remains (about 4–6 minutes). Strain the mixture into a heatproof bowl to remove shallot pieces; return the liquid to the bowl and let it cool slightly.

Clarify butter

Melt 6 tbs unsalted butter in a small saucepan over low heat until butter separates. Spoon off and discard the milky solids or pour gently, leaving the solids behind, to yield clarified butter. Keep warm but not hot.

Whisk yolks

In a metal or heatproof glass bowl set over (but not touching) a simmering pot of water (double-boiler), whisk together 3 egg yolks and 1 tsp cold water until homogenous. Add the reduced vinegar-wine mixture slowly while whisking. Continue whisking constantly until the yolks thicken slightly and become pale and silky (should coat the back of a spoon). Temperature should stay below 160°F (71°C) to avoid scrambling.

Emulsify

Remove the bowl from the heat. Very slowly stream in the warm clarified butter while whisking constantly to create an emulsion. Start drop by drop, then thin stream as the sauce thickens. If the sauce becomes too thick, whisk in a teaspoon of warm water to loosen. Stir in the remaining 1 tbs chopped tarragon, 1/2 tsp salt, and 1/4 tsp white pepper or pinch of cayenne to taste. Keep warm (not hot) until serving.

Adjust and hold

Taste and adjust seasoning with a little extra vinegar reduction or salt if needed. If the sauce begins to separate, whisk over very gentle heat or place the bowl briefly over the simmering water and whisk to re-emulsify.

Arrange the roasted lion's mane mushrooms on a warm plate or platter. Spoon a generous amount of warm béarnaise sauce over the mushrooms, making sure some sauce pools under and around them.

Garnish with 1 tsp chopped fresh chives and a small handful (about 1/4 cup) of microgreens or chopped parsley for color and freshness. Serve immediately.