Preheat your oven to 220°C/Fan 200°C/Gas 7. Scrub the potatoes sweet potatoes (no need to peel) and chop them into finger sized chips. Tumble the chips on to a baking tray. Drizzle over 1 tbsp olive oil. Scatter over some salt and pepper. Toss and arrange the chips in a single layer. Slide the tray into the oven and roast for 20 mins.

While the chips are roasting, pour the brown rice vinegar into a bowl. Add a good pinch of salt. Peel the onion and slice it into really thin rounds. Add to the bowl. Peel most of the skin from the cucumber (it can be bitter). Using a veg peeler, peel the cucumber into long ribbons, turning the cucumber as you go. Finely chop the seeded middle. Add to the bowl with the onions and scrunch together. Set to one side to pickle.

When the sweet potato chips have roasted for 20 mins, remove the tray from the oven. Turn the chips over. Place the black bean cashew burgers onto the tray. Slide back into the oven for 10 mins. After 10 mins, flip the burgers over and cook for a further 10 mins.

While the chips and burgers are roasting, roughly chop the lettuce. Cut the tomato into thin slices.

The potato chips should have roasted for a total of 40 mins and the burgers for 20 mins. The chips should be crispy and caramelised on the outside and soft and fluffy in the middle.

Divide the lettuce and tomato between two plates. Top each with a small handful of the pickled onion and cucumber, dizzling over some of the vinegar. Place a burger on top of each. Pop the remaining cucumber and onion on top. Serve with the potatoes on the side with a dollop of the tomato sauce.