Introduce the composition of Zitong shortbread in 300 words.

Zitong Crispy Cake, formerly known as Bo Cuizi, is a famous traditional Chinese pastry in Zitong, Sichuan, China, and one of the local specialties. Zitong shortcake is made of wheat flour, rapeseed oil, lard, first-class sugar, sesame, etc., using traditional technology and unique formula. Charcoal fire was used in the past, but now it is baked in an infrared oven. It has the characteristics of full moon shape, light yellow color, bright luster, uniform and clear lines, crispy and delicious, slag melting at the entrance and elegant aftertaste. Varieties have developed from a sweet taste in the past to eight kinds such as lemon, banana, pepper and salt. Suitable for all ages, long-term packaging. Different specifications, rich and exquisite. Known as food, the gift of top grade, Zitong is one of the two must-haves. It is a nutritious and hygienic convenience food for consumers to travel at home.

According to the way I used to watch my mother make shortbread, I first mixed a big bowl of mother powder for fermentation. After the mother powder was completely fermented, I put a proper amount of freshly ground wheat flour in a basin, poured it into it, and put some saccharin or salt according to my personal taste. Then I add water while kneading to completely knead the mother powder, flour and water into a dry, thin and moderate dough. Knead it and put it in a basin for the dough to ferment. Knead the dough for a long time, the dough should be dry and thin, and the pastry will be soft and crisp. After the dough is fermented, first take the dough to a clean table and knead it evenly, then roll it flat with a rolling pin to the right thickness. Roll out the dough and lay it flat on the table for a few minutes. At this time, you can clean a steamer and prepare some lotus leaves. Then spread sesame oil on the dough surface, and then sprinkle sesame, leek and chopped green onion evenly. After sprinkling, you can gently press it with your hand. Then roll the dough into a tube shape, and there is no need for a gap in the middle. Roll up the cylindrical noodles from the beginning, roll them into snail-shell-shaped balls and lay them flat in a steamer covered with lotus leaves. After about half an hour, put the steamer on the boiling pot and steam for about half an hour. Remember to put some cold water on the surface of the dough roll with your hands when you put it on the steamer, so as not to crack the steamed cake because of the dry surface. After the shortcake is made, let it cool for a certain period of time, then cut it into four pieces with a knife and you can eat it.