Quinoa burgers

1 Put the quinoa and stock powder into a pan, add 1 cup boiling water, return to the boil and cover. Reduce to a very gentle simmer for 15 min. Turn off and leave for 15 min, before uncovering and cooling.

2 Meanwhile, make the sauce: combine the yoghurt, parsley, capers and garlic in a medium bowl. Season with black pepper, cover and put in the fridge.

3 Pulse the mushrooms in a food processor until finely chopped, then transfer to a bowl. Squeeze excess moisture from the grated zucchini/courgette. Add to the mushrooms.

4 Spray a large frying pan with oil and put on a medium heat. Add the shallot and chilli flakes and cook for about 2 min until softened. Add the mushrooms and courgette and cook for 4 min or until tender and most of the liquid has evaporated. Transfer to a bowl and add the parmesan and quinoa; season with black pepper. Leave to cool completely, then stir in the egg and breadcrumbs. Cover and chill for 1 hr or until firm.

5 Shape the mixture into six 2cm thick patties, pressing firmly. Heat a large non-stick pan with spray oil over a medium heat and cook in batches for 3 min on each side or until golden brown. Spread the rolls with the sauce, then sandwich with the burgers, watercress and cucumber.