Zhang Chu had already thought about the problem of wool when he began to build Fugu, and the wool must be obtained from the Mongols.

By the time of Chongzhen, the Mongols had long lost their former prestige, and the Mongols, who had swept through everything with iron horses, were not only at a disadvantage in the battle with the Ming Dynasty, but also robbed and plundered the Mongols all year round. After Huang Taiji came to power, Jin Shi slightly changed his policy towards the Mongols. Through the means of affinity, a large number of Mongolian tribes took refuge in the Houjin and became the pawns of the Houjin.

The Later Jin were always uneasy about the Mongol tribes, and implemented a brutal policy of "reducing the number of Ding" against the Mongols. Even the Houjin, a tribe that had already submitted to the Houjin, set an upper limit on the number of men, and once the Mongol tribesmen reached the upper limit of "minus ding", the men in the tribe who were taller than the wheels had to draw lots to decide who would be killed, so as to achieve the goal of reducing the population.

There was also a division within the Mongolian tribes, some of them were frightened by the Houjin and surrendered to the Houjin, and some of them went to the Ming Dynasty, due to the economic recession of the Ming Dynasty, the support for the Mongols became less and less, and the tribes that threw themselves to the Ming Dynasty were greatly reduced. Some of the Mongols who could not survive even joined the ranks of the displaced people to find something to eat, and earlier Wang Jiayin's team included tens of thousands of Mongols.

Zhang Chu decided to take advantage of the current weakening of the Mongols, give them a way out, and pull them towards himself.

Before the opening, Zhang Chu found the Mongolians stranded in Fugu City, paid them wages and let them carry out investment promotion activities, promising that if they recruited Mongolians for trade, they would get a commission.

The half-starved Mongols saw the way to survive and walked into the grassland with the dry food sent by Zhang Chu. Zhang Chu did not disappoint them, and took out a large number of scarce things on the grassland, salt, and cast iron pots, in exchange for the wool of the Mongols, cattle, sheep, and horses.

The Mongols also saw something new in the trade: food stamps. As long as you sell cattle, sheep, and horses to the stores of the security forces to get money, you can also get a corresponding number of food stamps, with which you can buy food in the stores exclusively operated by the security forces.

This was very exciting for the Mongols, and the Ming strictly controlled some of the Mongol trade. For example, iron and grain are prohibited items, and salt is also strictly controlled. Zhang Chu dared to sell iron because the security army had fully turned to the development of firearms, and simple cold weapons did not pose a threat to the security army, and converting castings into weapons did not save much trouble than making iron himself. Food stamps can only be obtained by selling cattle, sheep and horses, and the Mongols can only get grain after losing their cattle and sheep, and the total amount of food has not increased much, and the Mongols can also be controlled through grain stamps.

The Mongols saw the materials taken out by the security army and felt the sincerity of the other party's trade, and after the news was brought back to the tribe, more Mongols were attracted to Fugu with a large number of goods to trade. The security forces sent people to collect a small amount of taxes at the city gate, and then stopped collecting any fees, and also sent soldiers to patrol the commercial streets, and once they were discovered, they immediately punished them severely.

The favorable trading environment attracted more Mongolians to do business. Some Han Chinese shops in the Guannai saw business opportunities and ventured to Fugu under the temptation of huge profits. The market in Fugu suddenly prospered.

The goods produced by the security military factory with the trademark "Baoan" are very popular. Soft blankets, tight felt pads, and beautiful and sturdy floral fabrics are all necessities of life in the grassland. As long as you have cattle and sheep, you can exchange them in Fugu. For a time, the north of Fugu was crowded with people every day, and a large number of materials came and went here, and the reputation of Fugu Commercial Street gradually spread out.

The wool and horses urgently needed by the security forces were abundantly replenished.

After many days of busyness, Zhang Chu felt satisfied and decided to relax and get himself something delicious.

After arriving in Fugu, he couldn't go to Yue Yue's place to eat, Zhang Chu could only eat in the canteen with the guards, and Zhang Chu was full of resentment about the master's craftsmanship.

Zhang Chu prepared for this meal for a long time, first asked the craftsman to make a brass hot pot, and then asked the guard to buy charcoal, and he wanted to eat shabu mutton.

Zhang Chu was not satisfied, so he asked the guards to build a stove out of adobe in the yard, add charcoal fire to burn the furnace wall red, and then hang a whole pickled goat in the furnace, and after half a day of roasting, the delicious roasted whole sheep was baked.

Smelling the fragrance, the guards were already impatient, and when the roasted whole sheep was brought to the table, they were about to start with short knives in their hands.

Zhang Chu showed the majesty of the handsome, shouted to stop their uncivilized behavior, and asked for Sven to eat, Zhang Chu showed them the correct way to eat roasted whole sheep.

Before the water in the hot pot was boiling here, Zhang Chu put the slices of meat of different thicknesses cut by the guards into the pot. The mutton quickly changed color, and it was sandwiched out and dipped in the sauce, and Zhang Chu finally tasted the long-lost taste again.

The guards carefully put the meat in their mouths as Zhang Chu did, they were really afraid that the meat would not be cooked in such a short time. The delicious taste dispelled their concerns and unceremoniously feasted on them.

A gust of wind swept away Zhang Chu and the guards each ate a belly, the guards dispersed satisfied, Zhang Chu alone in the house recalled the taste, except for the lack of chili peppers, this pure natural mutton is more delicious than the later generations.

Zhang Chu decided to share this delicacy with the public, and asked the guards to pass on the order, and after some arrangement, the first restaurant in Fugu Shangmao Street opened, providing food for the past merchants, and also launched special foods, shabu mutton and roast whole sheep. The convenience of shabu mutton is very popular with merchants, and even brass hot pot is sold a lot.

Zhang Chu, who was full, came to be motivated, he transferred Li Yi, and another major expansion of the security army began. The young and strong among the homeless people signed up for the army one after another under the temptation of the lucrative treatment of the security army. There were also a large number of Mongols mixed in, and the security forces did not discriminate against them, no matter where they came from, as long as they met the conditions.

The Mongols are a people on horseback, and their skillful riding skills are admired by many veterans of the cavalry of the security army.

Li Yi blossomed at this time, and recruited thousands of recruits into his cavalry team at once, and the cavalry of the entire security army reached nearly 10,000.

Zhang Chu was secretly glad that when he started recruiting troops, he stipulated that the cavalry could not exceed 10,000, otherwise Li Yi would recruit more. The cavalry was simply too expensive. Zhang Chu didn't want to spend all his money on cavalry, he also needed infantry to defend his sphere of influence. So more than 10,000 infantry were recruited. The number of soldiers of the security army was almost 30,000, and the infantry were distributed to various places with a small number of cavalry after simple training to defend the victory of the security army, and most of the cavalry remained in Fugu to continue training.

The large expansion of the security army caused Hong Chengchou's dissatisfaction, he decided that Zhang Chu would be opposed, and sent people to secretly monitor the security army's every move for a long time, the security army's large-scale expansion confirmed his conjecture, he knew that he couldn't wait, once the security army was full of wings and wanted to exterminate it, it would be difficult, he immediately made a decision, and led his troops to kill the security army without asking Yang He for instructions, preparing to exterminate all the security forces.