Whisk together egg and heavy cream and set aside.
Place flour, sugar and salt in food processor and mix.
Turn food processor off then add butter.
Pulse 10-15 times until butter and flour mixture turns into cornmeal consistency.
Turn food processor on low then slowly add egg mixture.
Remove from food processor when 2/3 of ingredients forms a dough.
Sprinkle flour over a clean dry area then tip dough mixture out onto it.
Knead dough into a mound then pat into a circle.
Wrap pastry in plastic wrap and place in the fridge for 30 minutes.
Using the base of one of the tartlet pans, cut out circles of parchment paper to be placed on the base of each tartlet pan, then set aside.
Remove pastry from fridge.
Rub butter all over the inside of each tartlet pan and set aside.
Sprinkle flour over a clean dry area then roll pastry out, keeping its circular shape, until the diameter measures approx. 14 inches.
Using one tartlet pan score around it with a knife making sure to allow extra so that the pastry hangs over the tartlet pan.
Repeat until you have used up all of the pastry.
Place pastry sections into each tartlet pan making sure to carefully push pastry into base.
Roll rolling pin over the top of the tartlet pan to remove the excess pastry.
Form another circular mound with the excess and leftover dough.
Roll dough out to similar thickness as previous batch and repeat instruction 14-17
Place parchment paper circles on top of pastry in each tartlet pan, then place as many pie weights that can fit on top.
Place tartlet pans on a large baking sheet and bake blind in a preheated oven at 350 for approx. 30 minutes until pastry begins to golden.