Pre-heat the oven to 180ºC (350ºF) Gas 4. If you are using pecan nuts, place them on a baking sheet and toast lightly for about 10 minutes. Roughly chop and leave to cool. Meanwhile, line a 23 x 13 cm (9 x 5 in) loaf tin with a greaseproof paper liner. If you are making muffins then you will require 24 muffin or cupcake liners. In a medium bowl, cream the butter and sugars until light. Add the eggs a little at a time, beating well after each addition. Add the vanilla extract. Combine the flour, ground almonds, baking powder, baking soda, xanthan gum and salt in a medium bowl. Mash the bananas. Add the bananas to the butter and sugar mixture and stir. Add the flour mixture alternately with the buttermilk, mixing well with each addition. Pour the mixture into the prepared tin (or muffin tins). Bake for 45 minutes for a large loaf or 12–15 minutes for muffins. The loaf or muffins are ready when a wooden skewer inserted in the middle comes out clean. While the bread is in the oven make the icing. Combine the lemon juice with the icing sugar to make an opaque liquid. It should pour easily off a spoon but not be too liquidy. Adjust to the right consistency by adding more sugar or lemon juice as required. When the bread is ready, remove from the oven and allow to cool for about 10 minutes. Drizzle the icing on the bread or muffins and allow to cool. If you are freezing the bread, then do not ice it. Take it out of the freezer and allow it to defrost before icing. This recipe will make about 100 mini muffins. Bake for about 7–10 minutes in the oven. Note: If you are making this for young children, please omit the chopped nuts and replace with sultanas, raisins or chocolate chips
I recently tried these substituting 50g of the gf flour with white teff flour. If you haven't got teff flour, you could try adding buckwheat instead. You can also substitute milk for the buttermilk in the recipe by adding 1 tsp of white vinegar to 175 ml of semi skimmed or whole milk.