Why is the sugar surface thinner and thinner when frying sugar cakes?

The thinner the sugar noodles are when frying sugar cakes, the reason is to use warm water to mix the noodles, and then add sugar after waking up. The practice is as follows:

Raw materials of sugar cake:

Wheat flour 300g, self-raising flour 300g, brown sugar 150g, peanut oil.

Making method of sugar oil cake:

Step 1: Mix the dough.

1. Mix the flour and self-raising flour together, leaving one third, and make the rest into soft dough with warm water of about 35℃, and let it stand for 30 minutes.

2. Put the brown sugar in a container and turn off the fire with boiling water. When the temperature of sugar water drops to about 35℃, it is used to turn another third of the flour into a very soft dough and let it stand for 30 minutes.

Step 2: Fry sugar cakes.

Heat the wok on the fire and add a catty of peanut oil; Spread some peanut oil on the panel, divide the dough into small pieces, put some oil on the rolling pin, put a brown sugar dough on a white dough, roll it into a round pancake, cut it three times in the middle with a knife, then thin it by hand, with the sugar side up, put it in a 70% hot oil pan and fry it until golden, turn it upside down for a while, and take out the oil control.