Using an electric mixer with a paddle, mix the dry ingredients and add the butter in pieces, then slowly add the egg yolks. When the pastry comes together, remove from the bowl.
Divide the pastry into workable amounts. Cover with plastic wrap and chill to a workable temperature. (Note: This pastry can be frozen).
Below: Example using 650 grams of dough.
Preheat the oven to 180 C (360 F).
Roll the pastry out to 5mm thickness and butter a 20cm x 5cm (8in x 2in) flat tin. Line the tin with the pastry and then line the pastry with aluminium foil. Fill with pastry weights or beans and bake blind for 20 minutes or until the pastry is golden brown in colour. Allow to cool.
Pour your mix into the cooled pastry case, leaving a bit of room at the top and cook tart according to the recipe.