Step 1: The key is super cold butter to work with. Place whole sticks of butter into the freezer for 30 minutes so it is colder than the refrigerator temp, not to freeze it.
Cut the butter into 1/4-inch cubes and spread out on a plate. Put it back in the freezer to chill for another 15-20 minutes.
While the butter cubes are chilling, fill an 8-ounce cup or bowl with ice and ¼ cup of water and set aside or in the refrigerator to let that water get very cold.
Add the flour, sugar, and salt to a food processor. Pulse 2-3 times to mix the dry ingredients.
Take the butter cubes out of the freezer and immediately add them to the food processor. Process until the butter is in small chunks throughout the flour mixture.
Measure out ¼ cup of the ice water (with no ice) and sprinkle over the contents of the food processor. Process until the dough looks moistened but still crumbly, similar to a very dry cookie dough.
Lightly flour an open surface and empty the dough onto it. Lightly press the dough into a loose ball, then flatten it slightly to about 6-inch diameter. Wrap the dough in plastic wrap to completely cover and refrigerate for at least 30 minutes or until you are ready to use it.
Take the chilled dough out of the fridge, place it on a lightly floured surface and cut it so that one half is a little larger. Roll the larger piece evenly into a circular shape with ¼” thickness. Fit into the baking pan with a ½-inch overhang, and cut off the excess. Use the remaining dough to make the top crust strips.