Rub butter into flour, icing sugar, crushed cardamom seeds, and salt until crumbly. Stir in egg yolk and cold water until dough just comes together.
Shape into a disc, wrap, and chill in the fridge for 30 minutes.
Roll out to 2–3mm thick. Line a 23cm tart tin, trimming edges. Chill again for 20 minutes.
Heat oven to 180°C (160°C fan). Line pastry with parchment, fill with baking beans, and bake for 15 minutes. Remove beans and bake 5–8 minutes more until base is pale golden. Leave to cool and make the filling.
Beat butter and sugar until pale. Add eggs one at a time. Fold in ground almonds, flour, and almond extract.
pread lingonberry jam over pastry base. Spoon frangipane on top, smooth surface, and scatter with flaked almonds.
Lower oven to 170°C (150°C fan). Bake for 30 minutes, until golden and set in the centre. Cover loosely with foil if browning too quickly.
Remove from oven. Brush top with honey and put back in oven for a further 5-10 minutes. It should be just set in centre when done.
Cool in tin, then dust with icing sugar before slicing.