Preheat the oven to 180ºC, gas mark 4. Place the loaf cases on a baking sheet.
Whisk the butter and sugar together in a bowl until pale and fluffy. Whisk in the eggs, one at a time. Gently whisk in the 100g marmalade.
Mix together the flours, baking powder and poppy seeds and stir into the butter mixture. Fold in the almonds and spoon into the cases. Bake for 20-25 minutes until golden and cooked throughout.
Mix the remaining 1 tbsp marmalade with 1 tsp water and brush over the loaves while warm. Allow to cool.
Make ahead and freeze for added convenience.