Preheat the oven to 410 (F).
In a medium oven safe bowl, combine 6 tablespoons unsalted butter, 3 tablespoons water, 1 tablespoon vegetable oil, 1 tablespoon sugar, and a pinch of salt.
And now, this is going to sound really weird, but place the bowl in the preheated oven for 15 minutes, until the mixture is boiling and the butter starts browning.
After 15 minutes, remove from the oven (but keep the oven on!), and add 6 ounces of all-purpose flour by quickly spooning in flour in 1 tablespoon sized chunks. Use a heatproof rubber spatula to stir in the flour. As you do this, the mixture is also going to bubble and smoke, but trust the recipe! It works, I promise. The end result is a dough that pulls off the sides of the bowl and looks a little bit like a lump of mashed potatoes.
Once the dough is cool enough to touch, transfer the ball of dough into an 8-inch tart pan. Use the back of your hand to flatten out the dough onto the bottom of the pan, and your fingertips to mold the dough up into the corners and sides of the pan. It's going to feel really greasy and kinda unpleasant, but go with it. Once the tart dough has covered the pan completely, use a fork to poke several holes into the crust.
Bake at 410 (F) or until the crust is light brown and starts to appear flaky around 15 minutes. Remove carefully from oven and let rest on a wire rack.