Combine the flour, salt, sugar and butter in the bowl of a food processor. Process until the mixture resembles coarse sand. The dough should hold together when squeezed. If too dry, add 1 - 2 Tablespoons milk.
Pour dough into a greased 10 inch removable bottom tart pan.
Press the dough into the pan to form a shell. Cover with plastic wrap and refrigerate for 30 minutes.
Pre heat the oven to 350 degrees.
Remove the pan from the refrigerator and bake the tart shell for 30 minutes - until the crust is golden brown.
Remove and let cool.
Reduce the oven heat to 300 degrees.
For the filling:
Combine the eggs, sugar, salt and vanilla and beat with a whisk until combined. Add the drained greek yogurt and stir to combine.
Pour the filling into the baked tart shell and bake for 15 to 20 minutes or until the filling is set.
Toss the berries with the sugar and serve with the tart if desired.