- Preheat oven to 180C. Position oven rack in middle of oven.
- Line the base of a 20x30 centimetre sponge roll tin with greaseproof or baking paper.
- In a large bowl mix the oats, coconut, flour and sugar.
- Melt the butter and stir into dry ingredients until all is well mixed.
- Turn into prepared tin and press in with flat of hand or back of a spoon.
- Bake at 180C 25-30 minutes or until golden and set.
- Remove from oven, cool a few minutes, then with a sharp knife cut into squares.
- Leave in the tin to go cold, then remove carefully and store in an airtight container.