How long do you cook frozen chicken in the oven?

It takes an hour at 425 degrees. Just put them in a pyrex, season them on both sides, add olive oil or water (or a mixture of both) to add moisture to the chicken & cover the pyrex with foil. Preheat the oven to 425 & give it an hour, you'll have nice tasting, tender, & moist chicken breats.
According to the USDA it is safe to bake (in the oven) frozen chicken. Simply add 50% of the normal time it would bake. So if you're cooking a whole chicken that is about 3 pounds, you'd normally cook it thawed for 1 hour. So frozen you'd cook it for an hour and 1/2.

You need to be vary careful however. You can end up with a burned chicken that's still raw in the middle. Be sure to check the temperature of the flesh with a thermometer in several places and make sure it's 165 or higher in all the parts of the chicken. If at all possible thaw the chicken at least partially.