Sweet potato & chickpea burger

Mash 100g steamed sweet potato with 100g canned chickpeas (drained) in a bowl until smooth. Add 1 tsp breadcrumbs, pinch ground cumin, ½ tsp ground coriander, ½ garlic clove (crushed) and 1 egg white. Mix until well combined. Season with salt and pepper and form into a patty. Pan-fry patty in 1 tsp olive oil until golden. Top base of 1 x 40g multigrain bread roll (split) with ½ cup mixed salad leaves, cooked patty, 2 slices tomato and ¼ Lebanese cucumber (sliced). Serve with 1 tbs 99% fat-free plain yoghurt and roll top.