In a large bowl, mix together the flour, salt, and baking powder.

Cut the very cold vegetable shortening and butter into 1/2-inch cubes and add them to the flour mixture. Using either a pastry cutter, a fork or your fingertips, blend the butter and shortening into the flour. Cut it in until they are roughly pea sized. Pour 1/4 cup of the ice water into the mixture, and, using a fork, blend the water into the mixture. You just want everything to come together enough to stick together. Add more water if needed, 1 tablespoon at a time, just until the dough holds together. Turn the dough out onto a piece of plastic wrap, wrap up and refrigerate for 30 minutes.

Put one rack in the oven in the center, and the other rack one notch below the center. Preheat the oven to 400F.

*Roll the dough out to a 12-inch circle that is approximately 1/4-inch thick. Transfer the dough to a 9-inch tart pan. Press the dough into the tart pan, folding back the edges a bit to form a crust. Feel free to patch up any spots that need patching. Refrigerate the crust for 30 minutes to prevent it shrinking while baking.

Remove the crust from the refrigerator and prick generously with a fork. Cover it completely with a piece of aluminum foil, shiny side down, and put pie weights or dried beans on top of the foil. Blind bake the crust in the preheated oven for 20 minutes.

Meanwhile, toss the tomato slices with the olive oil and season with salt and pepper. Lay them in a single layer on a baking sheet and place them on the rack below the middle rack and roast for 15-20 minutes. Remove from the oven and set aside.

When the crust has cooked for 20 minutes, remove from the oven and remove the foil and beans. Return to the oven and cook an additional 5 to 10 minutes, until the crust is golden brown.

When the crust has browned, remove from the oven and evenly sprinkle the Parmesan over the crust. Using a slotted spoon or tongs, remove the roasted tomatoes from the pan and arrange them in a single layer in the crust. (Leave the juices behind.) Arrange the mozzarella over the tomatoes, then top that with the bacon crumbles. Return the pie to the oven and bake until the cheese is melted and browned, about 30 minutes.

Sprinkle the tart with the basil, and allow to cool for 5 minutes before removing from the pan.

*For easier transfer to the tart pan, roll the dough out on a silicone mat, a piece of plastic wrap or a piece of waxed paper. Then you don't have to worry about your crust sticking to the counter, and it's easier to transfer over without breaking the crust.