Deep Frying Chicken - how long?

As with most things, it will depend. Your variables are size, internal temp to start and frying temp.

Most recipes call for frying at 350 degrees, but for bone-in chicken (not counting wings), I find this too high - crust is way overdone by the time the meat is cooked.

I start at 350 and drop to 325 once I drop the basket. Large bone-in bone-in breasts should be butterflied at the thickest part.

I remove pieces from seasoned buttermilk and let them drain on a wire rack in a sheet pan for 20-30 minutes, then dust them (seasoned flour only) and let them sit for at least 30 minutes more. Just before frying I do the final breading - flour > egg/hot sauce/milk mixture > flour. This sitting out for 1-2 hours does two things: (1) raises the internal temperature of the chicken, so it will cook faster, and (2) removes moisture from the skin so the crust will adhere nicely.

Flip the pieces every 2-3 minutes - chopsticks are handy for this. When they float, they're done or damned close. Have the oven on in case you under-cook them until you get the hang of it. Mine are usually done in 10-12 minutes. Drain on newspaper.

Wings can and should be fried hotter. I peg the thermostat (375) and drop to 350 once they're in. Season with S&P and dust with cornstarch. Toss in hot sauce and butter when done.

Have fun!