Separate the eggs so the whites and yolks are in two different bowls and allow to come to room temperature
Preheat oven to 350°F
Prepare the Pastry Case
Roll out the shortcrust pastry until it is slightly larger than your tart case
Blind bake the pastry case for 12-15 minutes or until starting to turn golden
Make Raspberry Puree
Put the raspberries in a saucepan with ¼ cup sugar and 2 tablespoons of water
Heat over a medium heat, stirring occasionally until the raspberries break down. You can use a potato masher to break them down completely
When the raspberry puree begins to boil, remove from the heat and strain through a sieve into a bowl to remove the seeds. Leave it to cool slightly
Make the Raspberry Curd
Take the strained raspberry juice and pour it back into the saucepan along with the remaining sugar, lemon juice and salt
Stir together and cook until it thickens and large bubbles begin bursting on the surface. Remove from the heat
Slowly add two tablespoons of the raspberry mixture to the bowl with the egg yolks and stir until combined - this will temper the yolks. Then add the yolks into the remainder of the raspberry mix and stir together
Pour the raspberry curd into the baked pastry case and set aside
Make the Meringue
Whip the egg whites and cream of tartar on high until soft peaks form
Gradually add the sugar, one tablespoon at a time, continuing to whip in between each addition
When you are halfway through adding the sugar, add the cornstarch and salt. Continue to add the sugar until it's all in and the meringue is thick and glossy
Spread the meringue mixture over the raspberry curd. Make sure you push the meringue all the way to the edges so it touches the pastry and seals in the curd. Use a knife of spatula to make peaks on top of the meringue to add texture
Bake for 15-20 minutes or until it is as brown and crispy as you want it to be
Remove from the oven and let cool for an hour before transferring to the fridge. Chill for 1-2 hours before serving. This pie is best eaten on the same day as meringue doesn't hold up very well over time.