Hamburgers are relatively easy to make; to be precise, they're fast food, known for being simple to cook and tasty.
When Chen Ze just graduated from college and started working, due to his low salary, he would cook for himself to get by. However, at that time, his cooking skills were on par with Betty's current abilities.
But a person can't really poison themselves to death, and besides, constantly ordering takeout was too expensive, so that wasn't a sustainable solution in the long run.
And eating instant noodles all the time wasn't good for his health, so Chen Ze was quite troubled during that period. Eventually, he had an epiphany and started making hamburgers. As long as he bought the bread, the rest was easy to come by.
"Watch closely, this patty, just fry it for seven minutes, don't overdo it," Chen Ze demonstrated to Betty, and then put the sizzling patty on a plate.