Preheat oven to 170°C/325°F/Gas Mark 3
Beat butter and sugar together until it looks light and fluffy.
Beat in eggs gradually to butter and sugar mixture and add lemon juice.
Mix together flour and ground almonds. Then fold in almond and flour mix until fully combined.
Spread the raspberry jam evenly on the pre-prepared pastry shell.
Spoon in frangipane mixture and gently spread evenly in the tin.
Push the raspberries into the frangipane filling. Place the raspberries evenly in the tin leaving space between each to allow the frangipane to rise during baking. Sprinkle with flaked almonds.
Bake in the oven for 55-60 minutes until it is a light golden brown. remove from the oven and leave to fully cool before serving. (Check the frangipane with a skewer and that it comes out clean. Some oven temperatures may vary so be sure that the center is fully baked before removing it from the oven).
Once fully cooled dust with a little powdered sugar if desired.