Fry bacon in a large skillet over medium heat until crispy. Remove bacon and drain the fat, reserving one tablespoon of the grease in the skillet. Add the olive oil, onion, red pepper flakes and garlic. Cook and stir over medium heat until the onions are starting to be tender.
Add the bok choy, and place a lid on the pan. Let cook for 3 to 5 minutes. Remove the lid; cook and stir until the bok choy is tender but still crunchy, about 2 minutes. Stir in the bacon, and season with salt. Serve piping hot!
