For the pastry, place the flour, salt, sugar, butter and almonds into a food processor and pulse until the mixture resembles breadcrumbs.
Add the eggs and egg yolks one at a time and pulse until a smooth dough is formed.
Wrap the dough in cling film and chill in the fridge for half an hour.
Preheat the oven to 180C/360F/Gas 4.
Grease and flour a 23cm/9in loose-bottomed tart tin.
Unwrap the chilled pastry and roll out onto a cold, floured work surface. (NB: this is a very 'short' pastry and at first will be difficult to handle).
Line the tart tin with the pastry and trim off any excess. Prick the base with a fork, then cover the pastry lightly with some baking parchment. Cover the parchment with baking beans or uncooked rice and place into the oven to bake blind for 15 minutes.
Remove from the oven and remove the baking beans or rice and the baking parchment and set aside to cool. If the pastry base is still a little raw, return to the oven for a minute or two to dry out.
Reduce the oven temperature to 165C/330F/Gas 2.
Meanwhile, for the filling, place the ground almonds and caster sugar into a bowl and mix well.
Add the beaten eggs and almond essence and mix well.
When the pastry has cooled spread a generous layer of raspberry jam onto the pastry base.
Pour the filling mixture over the raspberry jam to fill the pastry case.
Top with flaked almonds, then bake in the oven for 25-30 minutes, or until the filling is baked through and golden-brown all over.
Remove from the oven and allow to cool. Serve warm or cold.