Asparagus-Sherry Vinegar Beurre Blanc with Poached Morel Mushrooms

Ingredients

• ▸450 g fresh asparagus, woody ends snapped off and reserved, tips cut into 4 cm pieces
• ▸80 ml sherry vinegar (Vinagre de Jerez Reserva preferred), divided
• ▸60 ml dry fino sherry
• ▸2 medium shallots, finely minced
• ▸1 clove garlic, smashed and peeled
• ▸150 g fresh morel mushrooms, halved lengthwise and gently brushed clean
• ▸225 g cold unsalted butter, cut into 1 cm cubes
• ▸1 tsp kosher salt, plus more to taste
• ▸0.5 tsp white pepper, freshly ground
• ▸1 tsp fresh tarragon leaves, finely chopped
• ▸1 tbsp fresh flat-leaf parsley, finely chopped
• ▸0.5 tsp smoked sweet pimentón (Spanish smoked paprika)
• ▸200 ml cold water, for asparagus stock

Instructions

1. 1

   1. Make the asparagus stock: Place the snapped-off woody asparagus ends in a small saucepan with 200 ml cold water, a pinch of salt, and the smashed garlic clove. Bring to a gentle simmer over medium heat and cook uncovered for 15 minutes until the liquid reduces by half and tastes intensely grassy-sweet. Strain through a fine-mesh sieve, pressing the solids firmly; discard solids. You should have roughly 80–100 ml of concentrated asparagus stock. Set aside.

2. 2

   2. Build the sherry reduction: In a wide, heavy-bottomed saucepan (stainless or enameled — avoid reactive aluminum), combine the minced shallots, 60 ml of the sherry vinegar, and the fino sherry. Bring to a brisk simmer over medium heat and reduce until only about 2 tablespoons of syrupy liquid remain and the shallots look jammy, about 6–8 minutes. Do not let it scorch.

3. 3

   3. Add the asparagus stock: Pour the warm asparagus stock into the sherry reduction. Stir to combine and return to a gentle simmer over medium-low heat. Let the combined liquid reduce by one-third, about 3–4 minutes, until it smells like a Spanish spring garden. Season lightly with a pinch of salt and the white pepper.

4. 4

   4. Poach the morels: Reduce heat to the lowest setting. Add the cleaned morel mushrooms to the warm asparagus-sherry base. Poach gently — the liquid should barely shiver, never boil — for 4–5 minutes, turning the morels once with a spoon, until they are just tender and have released a small amount of dark, earthy liquid into the base. Remove the morels with a slotted spoon and set aside on a warm plate. Do not discard the now-enriched poaching liquid.

5. 5

   5. Mount the beurre blanc: Keep the pan on the lowest possible heat (or use a heat diffuser). Begin whisking in the cold butter cubes one or two at a time, waiting for each addition to be fully incorporated before adding more. The sauce will turn opaque, creamy, and pale golden. Work steadily — if the sauce looks greasy or breaks, immediately remove from heat and whisk in one more cold butter cube off the heat to re-emulsify. The finished sauce should coat the back of a spoon.

6. 6

   6. Finish and season: Stir in the remaining 20 ml of sherry vinegar (this brightens the sauce and reinforces the Spanish character — taste as you go and adjust). Add the pimentón, tarragon, and parsley. Fold the poached morels back into the sauce along with the reserved asparagus tips. Let the tips warm through in the sauce for 1–2 minutes; they should remain slightly crisp.

7. 7

   7. Serve immediately: Spoon over grilled white fish, pan-seared chicken breast, poached eggs on toast, or steamed new potatoes. The sauce does not hold well — beurre blanc is a live wire. If you must wait, keep it in a warm bain-marie and whisk before serving.

Variations

• ◆Bloom a small pinch of saffron threads in the fino sherry before reducing — it dyes the sauce amber-gold and adds a floral, medicinal note that doubles down on the Spanish angle.
• ◆Rehydrate 30 g dried morels in warm water for 20 minutes, then use the strained soaking liquid in place of part of the asparagus stock for a deeper umami backbone.
• ◆Mount cold-pressed Spanish olive oil using the same gradual whisking technique in place of butter — you get a loose, broken-style warm vinaigrette rather than a true emulsion, which is funkier and lighter and surprisingly convincing over grilled vegetables.