The only way to know for sure what breed would be papers on the cat. Any purebread would have papers, though a rescue might not depending where they got the kitty from. That's one beautiful girl!
An American Shorthair is actually a breed itself, and they have a type of tabby pattern
This kitty would be a domestic shorthair. Since DSH cats are a mix of many breeds and come in many colors, and patterns, there can sometimes be a more prevalent breed mixed in, there could be a bit of bombay mixed in, or another breed. Bombays' are pretty rare, not many of them around, so most likely this is DSH kitty, and a beautiful one
Brie is a beautiful kitty. If she was a pure breed she would have papers and have been gotten from a breeder. Welcome to you both. Someone here might have a better clue as to what type of kitty she is. You will love TCS, it is lots of fun and full of info. Welcome again.