Make a vegetable stock by pouring 500ml of boiling water from the kettle over 1 tbsp of dried mushrooms. Bring a deep pan of water to the boil then rain in 250g of pearl barley and bring it back to the boil. Lower the heat to a simmer and let it cook for 25-30 minutes till the grains are tender. They should still have a pleasingly chewy quality. Drain and set side.
Peel and roughly chop a medium-sized onion. Warm 4 tbsp of olive oil in a casserole or high-sided frying pan. Stir in the onion and leave to soften over a moderate heat with the odd stir. After 20-25 minutes it should be pale gold. Peel and crush 2 cloves of garlic and continue cooking for another few minutes.
Finely slice 600g of assorted mushrooms (split them into firm and tender depending on what varieties you are using). Add the mushrooms and cover the pan with a lid. Cook until the mushrooms are golden, adding a little more oil as necessary. Stir in 1 tbsp of tomato purée, cook for 2 minutes, then stir in 1 heaped tbsp of plain flour.
Add the dried mushrooms and their soaking water and bring to the boil then lower the heat, season with salt, black pepper and ½ tsp of dried chilli flakes.
Stir in the cooked barley and continue cooking for 7-8 minutes. Tear up a handful of basil leaves. Add the basil and any fragile mushrooms you kept to one side. Squeeze the juice from half a lemon and stir in, a little at a time, tasting as you go. Serve in shallow bowls. Enough for 4
Dried porcini are expensive but you can buy bags of mixed dried mushrooms – often broken pieces – at a reasonable price. Their deep umami goes a long way; you only need 1 tbsp of dried mushrooms to give you 500ml of rich, bosky stock.
Wheat berries would be an interesting substitute for the barley, but take longer to cook – about 40 minutes.
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