Step 1

Preheat oven to 180C/160C fan forced. Line 2 baking trays with baking paper. Use a sharp knife or mandolin to thinly slice sweet potato and beetroot. Spread evenly on prepared trays. Lightly spray with oil. Sprinkle with half the sumac and cumin. Bake, swapping trays halfway through, for 25-30 minutes or until golden and crisp.

Step 2

Meanwhile, finely grate 1 zucchini. Squeeze out excess moisture. Place in a bowl with chicken, carrot, shallot, parsley, remaining sumac and cumin. Season with pepper. Mix well then shape into 4 patties.

Step 3

Preheat a barbecue grill or large chargrill pan on medium-high. Cut each remaining zucchini into 4 thick slices. Lightly spray patties and zucchini with oil. Cook patties for 4-5 minutes each side or until cooked through. Cook zucchini for 1-2 minutes each side or until just tender.

Step 4

Spread bread halves with tzatziki. Top each with rocket, a patty, sauerkraut and zucchini. Serve with sweet potato and beetroot chips.