Flaky Gluten-Free All-Butter Pie Dough (Whole-Grain + Gum-Free)

INGREDIENTS

6 tbsp

ice water (from 1 cup ice cubes filled with cool water)

1/2 cup

/ 80 grams) sweet white rice flour (mochiko)

1/4 cup

plus 2 tablespoons (1.25 ounces / 35 grams) GF oat flour

1/4 cup

/ 35 grams) millet flour

1/4 cup

cornstarch (1 ounce / 30 grams)

2 tbsp

/ 15 grams) tapioca starch/flour (same thing)

2 1/2 tbsp

/ 15 grams) finely ground chia seed

1 tbsp

/ 15 grams) sugar

1/2 tsp

fine sea salt

8 tbsp

/ 115 grams) cold, unsalted butter (preferably European-style such as Straus), sliced ¼" thick

1 tsp

apple cider vinegar