Line an 8x8 or 9x9 square baking dish with parchment paper. Preheat oven to 325.
For crust: Mix together the melted vegan butter, sugar, flour, vanilla and salt. Pour into the baking dish. Using floured fingeres press the crust evenly into the dish.,
Bake the crust at 325 for 15-20 minutes. You want the edges lightly browned. The crust will be tender coming out, that's ok.
In a large mixing bowl, which together the lemon, vegan butter, vegan eggs, sugar, starch, salt and flour. Pour the lemon mixture over top the baked crust.
Bake lemon bars for 25-35 minutes at 325 degrees. I baked mine for about 35 minutes just to be sure, but 30 minutes is really the sweet spot for baking these.
Pull from oven and allow to cool for at least an hour - ideally two hours or overnight.
Just before serving, sprinkle powdered sugar over top and then slice into squares.