Is it safe to first make sautéed onions and then cook raw (thawed) beef in the same pan? I plan on cooking the meat thoroughly (no pink), so I figured I should be okay, right?
As long as you cook the meat thoroughly (i.e. if it reaches a safe temperature), most pathogens should be dead and it doesn't matter in which order you put the vegetables and the meat in. However, the order does matter if you don't want to have your garlic or onions burned while the meat is undercooked or raw vegetables while the meat is overcooking.