1 Using clean hands, combine the mince, sweet potato, lemon zest, ½ teaspoon of paprika and 2 tablespoons of chives in a large bowl. Shape into four round patties. Cover patties and place in the fridge for 20 minutes.
2 Heat a barbecue hotplate or a chargrill pan over high heat. Spray patties and mushrooms lightly with olive oil. Cook for 4–5 minutes each side, or until patties are cooked through and mushrooms are lightly charred and tender.
3 Meanwhile, combine roasted capsicum, the chilli flakes, lemon juice, olive oil, and the remaining chives and paprika in a medium bowl. Season contents with freshly ground black pepper.
4 To serve the burgers, top a mushroom with cucumber and carrot ribbons, salad leaves, a patty and a dollop of capsicum salsa. Top with second mushroom and serve with extra salad leaves.