1.Make cashew dip: Soak cashews in water for 3 hours; drain. Place drained cashews in a high-powered blender with garlic, rind, juice and the water; blend until smooth. Season to taste. Just before serving, stir in mint.
2.Combine kohlrabi, kumara, brown rice flour, green onion, coriander, LSA and combined egg whites and the water; mix well. Season. Shape mixture into 8 portions.
3.Heat half the oil in a large frying pan over medium-high heat; cook rösti, in two batches, for 5 minutes each side or until golden.
4.Serve rösti with cashew dip.
You will need to soak the cashews for the dip in water for 3 hours before you start this recipe. LSA is a ground mixture of linseeds (L), sunflower seeds (S) and almonds (A); available from supermarkets and health food stores. Rösti can be made a day ahead; store, covered, in the fridge.