1. Beat the egg yolks into the basin, and use an electric whisk until the volume is enlarged and the color becomes lighter.
2. Weigh the flour and sift it.
3. Pour the flour into the egg yolk and stir evenly with a spatula. Put it into a disposable piping bag and squeeze it into the baking tray. (Put a piece of greased paper in the baking tray)
4. Preheat the oven and heat it up and down to 170 degrees for 15 minutes.
Tips:1. In order to test the difference between beaten egg yolk and un beaten egg yolk, I made two kinds of them. The results show that the swelling is big.
2. The egg yolk is a bit fishy, you can add a few drops of vanilla extract.
3. With this formula, the biscuits made are a little bit less, and you can add several times more raw materials according to your needs.
