To make the pie dough:

1. Whiz the flour, sugar, and salt in a food processor to combine (Note: you can also do this by hand with a pastry cutter!) Pulse in the shortening and butter, just until evenly dispersed with pea-sized clumps throughout. Begin adding ice water 2 tablespoons at a time until moist clumps begin to form. Remove dough from food processor, form it into a flat round disk, and wrap in plastic wrap. Chill in the fridge for at least an hour prior to use.

To prep the quiche:

1. Preheat the oven to 375 degrees. Use a floured rolling pin to roll the dough out onto a floured work surface into a round of dough about an inch and a half wider on all sides than a shallow 9” tart dish. Roll the dough back onto the rolling pin and the transfer it to the dish, unrolling as you go. Gently work the dough into the edges of the dish and trim off any excess dough, leaving about an inch of excess hanging on all sides.  Fold the dough under itself and gently crimp the edges into the dish, allowing the top of the dough to extend about ¾-1” above the lip of the dish. This will help keep your crust tall even after baking. If your dough has gotten soft or warm while rolling it out, place it in the freezer for 5-10 minutes to chill up again. 
2. When ready to bake, prepare your egg wash by whisking the remaining egg from the pie dough with a teaspoon of water. Place a crinkled sheet of parchment paper into the bottom of the crust and fill it with pie weights or uncooked dry beans. Bake in the preheated oven about 10 minutes, then remove the paper and weights, brush the entire crust with a thin layer of the egg wash, and bake for an additional 15 minutes, or until the bottom of the crust doesn’t look too wet and soggy. While the crust is baking, begin to assemble your filling.
3. In a small fry pan, heat the butter until melted and then cook the onion over medium heat, stirring regularly, until softened and translucent. Add the garlic and cook for an additional minute. Remove from heat and set aside. 
4. Whisk together the half and half, eggs, parmesan, Italian seasoning, basil, salt and pepper. When the crust is finished baking, spread the cooked onion mixture on top of the crust and evenly spread out the sundried tomatoes and feta. Carefully pour the egg mixture into the dish, being careful to not overflow the tart. Bake in the preheated oven for about 35 minutes or until the top is golden and the center is no longer jiggly. Serve warm or reheat individual slices in the toaster oven!