Mustard Prawns

Pat the prawns thoroughly dry with kitchen paper and season with fine sea salt and black pepper. Mince the garlic, dice the shallots, chop the tarragon and parsley, and zest and juice the lemon. Measure out the two mustards for the sauce and the two reserved finishing mustards separately into small bowls.

Place a large, heavy-bottomed skillet over high heat until the pan is smoking. Add 1 tbsp olive oil and 1 tbsp butter, then lay the prawns in a single layer and sear without moving for 90 seconds until deeply pink and lightly charred at the edges. Use tongs to flip each prawn and cook for a further 60 seconds until just opaque at the thickest part — target internal temperature 63°C on an instant-read thermometer. Transfer the prawns to a plate and tent loosely with foil.

Reduce the heat to medium and add the remaining 1 tbsp olive oil and 1 tbsp butter to the same pan. Add the shallots and cook, stirring frequently, for 3–4 minutes until softened and translucent, scraping up any browned bits from the prawn sear.

Add the garlic and cook, stirring constantly, for 60 seconds until fragrant but not coloured.

Pour in the white wine and simmer vigorously for 2–3 minutes until reduced by half and the sharp alcohol aroma has subsided.

Add the double cream and stir to combine. Simmer on medium-low for 2 minutes until the sauce is thick enough to coat the back of a spoon.

Remove the pan from the heat entirely. Stir in the 2 tbsp Dijon and 1 tbsp whole-grain mustard (the sauce base amounts) until fully incorporated, then stir in the reserved finishing mustards, the lemon zest and lemon juice — keeping the pan off the heat preserves the volatile mustard compounds that give the sauce its punch.

Return the prawns and any resting juices to the pan. Add the remaining 1 tbsp butter, the tarragon and half the parsley, and fold gently until the prawns are coated and the butter is melted into the sauce.

Transfer to a warm serving dish, scatter over the remaining parsley and a pinch of flaky sea salt, and serve immediately with crusty baguette or steamed rice.