For the jam, put a small plate in the freezer. Place about 250g/9oz raspberries (reserve 13 for decoration) in a deep pan and mash with a fork. Add the jam sugar and a squeeze of lemon juice. Heat gently until the sugar is dissolved.
Bring to the boil and then boil for about 5 minutes, or until a drop of the jam juice placed on the cold plate turns sticky. Once ready, place the pan in a cold water bath and set aside to cool.
For the pastry, beat the butter with a wooden spoon in large mixing bowl. Sift in the icing sugar, then add the ground almonds and salt and mix. Beat in the egg and vanilla paste, followed by the plain flour. Once combined to a dough, flatten to a disc, wrap in cling film and place in the fridge to chill.
For the poached pear, add the pear to a small saucepan with enough water to cover. Add the caster sugar, lemon juice and star anise. Bring to the boil and simmer for 5-10 minutes. Once tender, remove from the water and pat dry with kitchen paper, reserving the water.
Bring the reserved poaching liquid to the boil and then simmer for about 30 minutes to reduce it to a sticky syrup.
Take the pastry out of the fridge and roll to about the thickness of a £1 coin. Use the pastry to line a 23cm/9in tart tin. Prick the base with a fork, then spread a layer of jam on the bottom and leave to chill in the fridge.
Preheat the oven to 180C/160C Fan/Gas 4.
For the frangipane, put the butter and caster sugar in large bowl and blend using a handheld blender.
Beat the eggs with the Calvados, salt and the almond essence. Add a little of the egg mixture to the butter and sugar and beat until combined. Continue to add a little at a time and beat until smooth. Fold in the ground almonds and flour.
Carefully spoon the frangipane batter on top of the jam and then smooth the surface using a clean knife.
Quarter and core the pear. Cut each quarter into 3 even slices. Arrange the slices on top of the tart in a flower shape leaving a space between each slice. Place a raspberry in between each pear slice and one in the middle.
Bake for 45 minutes, or until cooked through. You may need to cover the tart with aluminium foil for the final 15 minutes to prevent it browning too much.
Remove from the oven, brush the reduced poached pear syrup over the top and set aside. After a few minutes slide onto a wire rack to cool. Serve warm or cold.