Hello rfc experts,

I want to do a beef stir-fry sometime this weekend, and need a bit of
advice. My questions a

1) What cut of beef is best for a stir-fry?

2) I have heard that whatever cut of beef I get, I should freeze it
first and then cut "across the grain" of the meat. Apologies for my
ignorance, but how does one determine "the grain" of the meat, and how
to cut against it? If someone could give a detailed description of
what directions the fibers in the meat should be as I'm slicing it,
'twould be much appreciated!

3) What is the best way to prep the beef for stir-frying after slicing
it up? I've seen references to "velveting" the meat with various
combinations of cornstarch and egg-white, and would especially
appreciate an explanation of the purposes of preparing meat for
stir-frying (whether marinating or otherwise).

Thank you, everybody, for your help!

Best wishes,

Adilah