How to Make It
Preheat the oven to 300°. In a small skillet, cook the butter over moderately high heat until deep golden brown, about 2 minutes. Remove the skillet from the heat.
In a medium bowl, whisk the flour with the sugar and egg whites until smooth. Whisk in the browned butter and hazelnut oil. Let the batter stand at room temperature for 1 hour.
Line a large baking sheet with a silicone mat. Spoon 6 teaspoons of the batter onto the baking sheet 3-inches apart. Spread the batter into 3 inch rounds. Bake the tuiles in the center of the oven, 2 baking sheets at a time, for 8 minutes, or until light golden, turning the baking sheets halfway through.
Drape the warm tuiles over a rolling pin immediately after removing them from the oven. Return the tuiles to the oven for 30 seconds if they become too brittle to bend. Repeat with the remaining batter.