1kg/2lb loaf tin, lined with parchment paper, or 24 small paper muffin cases
Preheat the oven to 180C/350F/Gas 4. Cream the lactose free butter and sugar together until pale, light and soft. Add the eggs, one by one, and beat well between each addition.
Mash the bananas and add to the creamed mixture. Sift the rice flour, cornflour, gluten-free baking powder and salt together and fold carefully into the banana mixture.
Pour the mixture into the loaf tin or into 24 small muffin cases and bake in the oven for about 1¼ - 1½ hours for the loaf, 25 minutes for the mini muffins, until golden on top and a skewer inserted into the centre comes out clean.
Remove the loaf from the tin and cool on a wire rack; cool mini muffins on a rack in their paper cases. Slice the loaf into eight slices to serve.