Step 1: Preheat your oven to 170°C (340°F) and grease a standard 2lb loaf tin, lining the bottom with parchment paper.
Step 2: In a large bowl, cream together the softened butter, caster sugar, and lemon zest until the mixture is light, pale, and fluffy.
Step 3: Beat in the eggs one at a time, adding a tablespoon of the flour with the last egg to prevent the mixture from curdling.
Step 4: Gently fold in the remaining all-purpose flour, almond flour, baking powder, and a pinch of salt until just combined.
Step 5: Stir in the lemon juice and half of the chopped pistachios, then pour the batter into the prepared tin and smooth the top.
Step 6: Bake for 45-50 minutes, or until a skewer inserted into the center of the loaf comes out clean.
Step 7: Allow the loaf to cool in the tin for 10 minutes before transferring to a wire rack. Once fully cooled, whisk the glaze ingredients together, pour over the loaf, and sprinkle with the remaining pistachios.