Heat 1 cup water in a non-stick pan. Add quinoa and bring to a boil. Reduce heat, cover and simmer for 15minutes or till the water is absorbed. Remove from heat and set aside for 5 minutes.
Transfer the quinoa into a food processor. Add edamame, 2 chopped spring onion with greens, egg, ginger, garam masala powder, salt and cayenne pepper. Pulse till well combined and transfer into a bowl.
Divide the mixture into 4 small thick patties.
Heat olive oil in a non-stick pan. Place the patties and shallow-fry for 3-4 minutes on each side.
To make yogurt sauce, mix together yogurt, cucumber, coriander leaves, crushed peppercorns, salt and remaining spring onion with greens in another bowl.
Apply some yogurt sauce on a tomato slice, place some lettuce leaves, a patty and cover with another tomato slice to make a burger.
Serve the burgers with the yogurt sauce.