1 1/2 kg kumara of your choice - the red ones hold together better during precooking than the orange ones do
3 large cloves garlic
1/4 cup rice flour
1/2 tsp salt
2 cups sour cream
1/2 cup milk
200 g grated cheese
1) Put a large pot half filled with salted water on the stove to boil. One at a time, peel the kumara, slice into 5mm slices and drop into a bowl of cold water, ensuring all the slices separate. When the pot is boiling, drain the kumara well, then drop into the boiling water and cook until just barely tender - about 7 mins for red kumara, or 5 for orange. Immediately drain into a colander.
2) Meanwhile make the sauce: chop garlic finely and place in a bowl. Add to it, mixing until smooth, the flour, salt, sour cream and milk.
3) Grease an ovenproof dish, about 23 x 30cm. Overlap half the kumara in it, drizzle half the sour cream mix over it, and then sprinkle with almost half the grated cheese.
4) Open a large can of your favourite fish - I used smoked fish - drain and tip into a bowl. Break it into flakes with a fork, then spread over the kumara/sour cream in the baking dish.
5) Repeat the kumara, sauce and cheese layers.
6) Bake uncovered at 180C (350 F) for about 30 minutes, until the mixture feels firm and the topping is golden brown. Allow to stand in a warm place for 5-10 mins before serving.
Serve with salad.