Preheat the oven to 200C/180C Fan/Gas 6 and line a 12-hole muffin tin with paper cases.
Sieve the gluten free flour and baking powder into a large mixing bowl. Add the sugar, almonds and lemon zest and mix well.
Beat together the milk, butter, oil, eggs, vanilla and lemon juice in a jug. Pour over the dry ingredients and mix together gently until the dry ingredients are just wet (don’t over mix or the muffins will be tough).
Divide the mixture between the cases (they should be about 3/4 full).
Bake for 15–18 minutes until a skewer comes out clean.
Quickly use a cocktail stick or skewer to poke holes in each muffin.
Combine the glaze ingredients straight away, then use a pastry brush or a teaspoon to cover the tops of the muffins. Repeat until all the glaze has been used.
Lift the muffins onto a wire rack to cool a little, before eating warm or at room temperature.