Begin by pouring the buttermilk into a large saucepan and bringing it to the boil. Continue to cook until the solids separate from the whey

Strain the whey into a clean pan and discard the solids. Bring to a simmer and reduce until you’re left with 200ml of whey

Meanwhile, stir the lemon juice into a large bowl of water. Peel the salsify and cut into 10cm-long pieces, placing them into the acidulated water immediately to prevent discolouration. Use a mandoline to very finely slice the salsify lengthways, to create noodles, then return to the acidulated water

Using a very sharp knife, cut the cuttlefish into noodles the same size as the salsify, then set aside

Once the whey has reduced to around 200ml, keep over a low heat and whisk in the diced butter a little at a time to form an emulsion

Plunge the salsify and cuttlefish noodles into the emulsion and cook for 1 minute, then lift out and divide between 4 dishes. Season, then finish with the sorrel and a little more of the butter emulsion. Serve immediately