Preparation

Make the pie crust: Add flour, granulated sugar, and salt to a food processor fitted with the blade attachment. Pulse a few times to combine. 

Scatter butter pieces over the flour. Pulse until the butter is cut into small pieces, and the mixture resembles coarse meal, with visible butter pieces no larger than a pea. 

Drizzle 3 tablespoons cold water over the flour mixture and pulse. Repeat adding a tablespoon of water at a time, until the dough holds its shape when a handful is squeezed together.

Remove dough from food processor and shape into a ball. Wrap with plastic and flatten into a disk with a rolling pin. Refrigerate at least 1 hour or up to 3 days.

Make the filling: Preheat oven to 350°. In a large bowl, combine the 2 cups chopped pecans, red bean paste, brown rice syrup, soy milk, brown sugar, melted vegan butter, potato starch, vanilla, and salt. 

Place chilled pie dough between two sheets of parchment paper. Using a rolling pin, roll dough into an 11-inch round. Transfer the dough into a 9-inch pie plate, using your fingers to gently pat the dough into place. Trim any excess dough with a paring knife or kitchen scissors, leaving a 1-inch overhang; then fold dough under to reinforce the edge.
To crimp the edges, hold a spoon upside down and press into the crust on the inside edge, then make a second indent by moving the spoon toward the outside edge, repeat one more time. Continue making indents all the way around to create a pretty scallop edge. 

Pour filling into crust and arrange whole pecans on top in a circular pattern. Bake until crust is golden and the pie filling sets and doesn’t jiggle too much, about 1 hour to 1 hour and 15 minutes. Let cool completely on a wire rack before slicing and serving.

NOTE: For a shortcut, skip the crust and buy vegan pre-made pie crust if you don't want to make the crust from scratch.