It is not enough to use only urea, which can be used with flour chips. The formula of large fried dough sticks with crisp outside and soft inside is: 9.5 kg of medium gluten flour, 0.5 kg of eggs, 50-60 g of flour chips, 50 g of food-grade ammonium bicarbonate, 20-60 g of sugar, butter (shortening or cream), 70- 100 g of salt and 5.7 g of 30-degree water. Technology: Mix flour and crispy noodles well. Add eggs, ammonium bicarbonate, sugar and salt to flour and water to melt. Add flour and butter to form dough. Do not knead the dough. Cover the dough with a wet cloth, stir-fry for 10 minute, knead once, stir-fry for 10 minute, knead again, knead into strips, wrap with plastic wrap, and ferment at low temperature for 6-8 hours. Take it out and shape it, fry it in a 200-degree oil pan, turning it constantly, and fry it until crisp.