Cook the freekeh according to the instructions on the pack. While the grain is cooking, in a separate pan add the lentils, 3 cups water, and the khombu and bring to the boil. Reduce the heat and simmer for approx 30 minutes until the lentils are tender. Discard the kombu.
Drain the freekeh and lentils of any excess water and place in a food processor. Process until they are well combined but retain texture.
Heat a small pan with olive oil. Add the onions and garlic and sauté for a couple of minutes until tender. Add the spices and cook for a further 2 minutes. Transfer the onion mix to a bowl with the lentil and freekeh. Combine thoroughly with preserved lemon, fresh coriander and seasoning.
Mould the mixture into flat patties (approx 8 cm x 2.5cm). Brush with both sides of the patties with olive oil and grill for 3 - 4 minutes each side.
Note: Freekeh is an ancient grain made by burning then rubbing away the outer husk of unripened wheat. It is available from health food stores and the health section of most leading supermarkets. Freekeh is not suitable for coeliacs.