First, make the pastry. Rub the flour, icing sugar, and butter together between your fingertips, until the mixture resembles breadcrumbs. Make a well and tip in the egg. Use a spoon/spatula to combine the egg.
Add a very small amount of milk and bring together to form a round ball of dough. Wrap in clingfilm and leave to rest in the fridge for about 30 mins.
Preheat the oven to 180oC and grease two cupcake tins.
When the pastry has rested, lightly flour a worktop and roll it out quite thinly. Use a small fluted cutter to cut out circles. Lightly press the pastry circles into the tins, then spread a small amount of jam onto the base of each one. Use about half a teaspoon of jam per tart.
To make the frangipane, cream the butter and caster sugar until soft and airy. Add the eggs one at a time, beating well. add a small amount of the ground almonds with the eggs. Then add the remaining ground almonds and fold in, incorporating plenty of air. Crush a few flaked almonds and lightly stir in, along with 2 drops of almond essence.
Place a generous teaspoon of the frangipane into each pastry case so that it completely covers the jam. Bake for about 10-15 mins until the pastry is cooked and the frangipane is golden and spongy.
Turn the tarts out onto a wire rack to cool.
Cut the glace cherries into heart shapes (cut a tapered sliver off each side, then a small triangle in the top – great tip from my 14-year-old brother, who cut the cherries for me!)
When the tarts have completely cooled, make some glace icing by mixing icing sugar with a small amount of water, until just runny enough to ice the tarts. Cover half the tarts with white icing and top with the cherry hearts.
Add some pink/red food colouring to the remaining glace icing and stir well. Use this to ice the remaining tarts, and arrange two almond flakes on each to resemble hearts.