potato gratin with sorrel recipe

The flavour of sorrel is excellent with potatoes, which absorb some of it's citrus taste. This is delicious with salmon or chicken.

For 4-6

• 30g unsalted butter, plus more for the dish
• 1kg potatoes
• 150g young sorrel leaves
• 250g sweet white onions
• salt
• 175ml double cream

Preheat the oven to 180°C/gas mark 4 and butter a 2-litre gratin dish.

Peel the potatoes and slice them lengthwise as thinly as possible - a mandoline is useful for this. Remove the stem from the sorrel, roll it up tightly and cut across to make thin strips. Thinly slice the onions.

Melt a tablespoon of the butter in a saute pan over a low heat. Add the sorrel, sprinkle with a little salt and cook for a minute, stirring with a wooden spoon, until the sorrel just begins to wilt. Add the cream and simmer for a minute. Remove from the heat.

Put the potatoes and onions in a saucepan. Add a good pinch of salt and pour over just enough water to cover them. Bring to the boil, cooking for 8-10 minutes, shaking the pan regularly to make sure they don't stick to the bottom. Take off the heat and drain. Pour a layer into the gratin dish, spread some sorrel mixture evenly over the top, and repeat.

Place in the preheated oven and bake for about an hour.

This recipe appears on p.91 of Sarah's Garden Cookbook.