1 and 1/4 cups (175g) plain flour (or a mix of wholemeal and plain)
1/3 cup + 1 tbsp (90g) cold butter
1 tbsp Natvia
1 egg, beaten
1 cup (175g) frozen raspberries
1-2 tbsp Natvia
2-3 tsp cornflour, it needs to be a fairly thick jam but not solid!
1/3 cup + 2 tbsp (100g) butter
3/4 cup (100g) ground almonds
2 tbsp (30g) Natvia
1 egg, beaten
2 tsp almond extract or Amaretto (more to taste if you want a strong almond flavour)
fresh or frozen raspberries, to serve
Preheat oven to 190C/375F/gas 5.
Make pastry: combine flour and butter in a mixer and pulse until the mixture resembles breadcrumbs (about 10 seconds), add Natvia and egg, and blitz until the dough just comes together, adding a little ice cold water if necessary. Bring dough into a ball with your hands, flatten into a disc and cover in cling film. Chill in the fridge for half an hour while you make the jam.
Make jam: Tip plums or raspberries into a saucepan with the Natvia and heat oven medium heat until the fruit starts to break down and the Natvia is dissolved. Mix the cornflour in a separate bowl with just enough water to make a paste, then whisk in to the jam mixture and allow to simmer until it is the desired consistency , checking on it and stirring regularly to make sure it doesn't catch (repeat cornflour process with additional cornflour if it is struggling to thicken). Pour jam into a cold bowl and allow to cool, then chill in the fridge while you bake the pastry.
Bake pastry: Roll out the chilled dough and line a lightly greased 23cm (9") tart tin with it (or 8 mini tart tins). Place greaseproof paper or tin foil on top of the pastry case and fill with ceramic baking beans or rice and blind bake in the preheated oven for 10 mins, until the sides are just starting to go a light golden colour. Remove the paper and beans, and put the pastry case back in the oven for another 5-10 mins, until the whole thing is lightly golden. Allow to cool while you make the frangipane.
Make the frangipane: Cream together all of the ingredients until you have a smooth, slightly grainy mixture.
Assemble the tart: Get your cooled pastry case and spread the jam in a thick layer on the bottom. Top gently with the frangipane (if you want to, piping it may help avoid the jam and frangipane mixing, but this is not necessary).
Turn the oven down to 180C/350F/gas 4 and bake the tart for 25-30 mins (0r 20-25 mins for mini tarts), turning halfway through so that the tart is beautifully golden all over.
Allow the tart to cool completely. Serve topped with fresh or frozen raspberries, either as they are or pushed through a sieve to make a coulis. Cream is also yummy with this!