Add the flour and salt to a large bowl and stir until well combined. Next, add the oil and stir until it is fully incorporated into the flour. You may have to use your hands for this part.
Once the oil is thoroughly mixed in, add the butter and use a pastry blender to chop the butter until it is the size of large peas. Make sure the butter remains cold and doesn't melt into the flour. Next, add the water and mix until the dough comes together. Flatten the dough onto some plastic wrap and shape into a rectangle, then wrap and refrigerate for 30 minutes.
After 30 minutes, take the dough out and place it on a lightly floured surface. Use a rolling pin to roll the dough into a large rectangle, about 14x8 inches. Next, fold the botom third of the short side up, then fold the upper third down on top of it, like folding a letter. Rotate the dough 90° and repeat the rolling and folding process twice more. Wrap the dough again and refrigerate for at least 1 hour or overnight.