Preheat oven to 350 degrees F.
Line 2 sheet pans with silicone sheet or parchment paper
In a bowl, place the flour and confectioners sugar. Mix until combined
Slowly add the egg whites, vanilla, and butter and mix with a whisk
The batter should be thick, like a pancake batter
In a smaller bowl, place the cocoa powder. Add about 2-3 tablespoons of the batter and mix until evenly combined.
Place the chocolate batter in a piping bag fitted with a small round tip and set aside
Spoon 1 1/2 teaspoons separated mounds of the white batter on the sheet pan. I was able to fit 4 or 5 in mine
White a small spatula or your index finger spread the batter thinly in a circular motion. Pipe the chocolate batter on top, use any design you may like: stripes, zigzag, squiggly lines, etc
Bake for 5-9 minutes (depending on your oven and the thickness you made the circles) until the outer edges of the tuiles start to turn brown
Remove them quickly from the oven and flip them over. Using the handle of a wooden spoon, roll them into a cigar, slide the cigar off and continue with the other ones. They will harden as they cool.
Let the tuiles completely cool on a cookie sheet and serve with your favorite ice cream
Store in a tight proof container at room temperature
Enjoy with ice cream