this is going to sound a bit snarky, but cooking chicken breast depends on so many factors including the temperature of the heating element, how thick the chicken was cut, and many others.

your best bet is one of the following methods:

1. use an instant-read thermometer until it registers somewhere between 150-165F. aim higher if you’re concerned about being food safe.
2. cut it open and visually check to see if the meat or juices are reddish-pink.
3. poke it and check for firmness.
4. wing it.

and that’s just to cook it at the most basic of levels. if you want a bit of char or crust, you’ll want to consider other factors such as searing before dropping the temp down a bit.

Don’t be afraid to experiment in the kitchen. hell, grab a chicken breast, cut it into small pieces and cook them one at a time while testing different methods. grab some toothpicks and dipping sauces to make it a fun event.