STEP 1/15
Whip egg whites to foam first.
STEP 2/15
Add sugar about 3 times and whip.
STEP 3/15
Please make a solid meringue.
STEP 4/15
Add the yolk and vanilla extract and whip.
STEP 5/15
Put the flour down on a sieve.
STEP 6/15
Mix gently so that the bubbles do not die.
STEP 7/15
Divide the dough into 7 pieces.
STEP 8/15
Add the food coloring and mix.
Add color and mix gently so that the foam doesn't die out too much when mixing.
STEP 9/15
Fill the piping bag with the dough.
STEP 10/15
After panning with red, orange, yellow, green, blue, navy, and purple
Bake in a 170 degree preheated oven for about 15 minutes.
STEP 11/15
Let it cool completely.
STEP 12/15
Add whipped cream and sugar and whip.
STEP 13/15
Spread whipped cream on the bread.
STEP 14/15
Roll it up and store it in the refrigerator for 30 minutes to an hour.
STEP 15/15
Cut it into appropriate thicknesses and it's done. :D