Put two tablespoons of oil in a large frying pan on a medium heat, add the onion and season generously.

While the onions start to cook, wash the chard and chop the stalks into 1-2cm slices, then add them to the onion pan and cook, stirring occasionally, for 10-15 minutes, until soft. If you can’t find chard, add one more onion to the sauce.

Finely chop the tarragon, reserve a small amount for the garnish, then stir the rest into the onion pan with the garlic and ancho, and cook for three to four minutes, until the garlic is soft.

Cut the chard leaves into thick 2-3cm ribbons, then stir into the onions with the sherry and cream.

Add a few tablespoons of water, cover the pan and leave to simmer gently for seven to eight minutes.

Put a second large frying pan on a high heat and add two tablespoons of oil and the butter.

Add the mushrooms and saute, stirring often, for 10-12 minutes, until they’re starting to turn golden, then tip into the onion pan.

While the mushrooms are cooking, cook the pasta according to the packet instructions in a pan of well-salted boiling water.

Drain, reserving a cup of the pasta cooking water, then add the pasta to the mushroom pan and, using a pair of tongs, toss and mix, adding a few tablespoons of the cooking water to bind the sauce into a silky-smooth emulsion.

Taste and adjust the seasoning, then serve at once, sprinkled with crumbled feta, a few toasted almonds, a drizzle of extra olive oil, the lemon zest and the reserved tarragon.