Step 1 Put chickpeas and half of the onion in a food processor with garlic, coriander, parsley, flour and egg white; blitz until almost smooth. Flour hands and shape chickpea mixture into 8 patties. Place patties on a plate, cover and refrigerate for 30 minutes.
Step 2 Set a large non-stick frying pan over medium heat. Add olive oil and heat. Add chickpea patties and cook for 4–5 minutes per side, or until cooked through.
Step 3 Meanwhile, prepare couscous according to packet instructions. Fluff cooked grains with a fork to separate; stir in lemon zest, mint, almonds and remaining onion.
Step 4 Mix yoghurt, tahini and lemon juice in a bowl to make dressing.
Step 5 Divide lemon–mint couscous among 4 plates; top with parsley falafel and tomatoes, drizzle with yoghurt dressing and serve.