Chocolate Banana Custard Éclairs Ingredients Éclair 4.75 ounces gluten-free flour (1 oz. superfine brown rice flour, 1 oz. superfine white rice flour,1 oz. GF oat flour, 1.75 oz. of tapioca starch) (about 1¼ cups) 1 teaspoon kosher salt 1 tablespoon sugar 2.75 ounces or scant ⅓ cup of unsalted butter 8 oz. (1 cup)