Sift dry ingredients together. Stir in egg whites and vanilla, then butter.
Spray parchment paper-lined sheet pan with pan release spray or use a silicone baking mat. Place a stencil on top. Using a small offset spatula, spread 1 Tbsp. batter into stencil. Carefully lift off and repeat with remaining batter. Bake in 375ºF standard oven 7 min. or until lightly browned. (The tuile will crisp while cooling.) Cool flat or use a wide spatula to immediately drape cookies over rolling pins. Cool completely and store in an airtight container.