For centuries, bacon was salted and dried enough that it could be stored at room temperature for extended periods. In those days before refrigeration, this was the whole purpose of making bacon and hams. Today, when these foods are cured for flavour, not preservation, they are finished at a higher level of moisture and require refrigeration or freezing to remain food-safe. Usually, only a minimum of planning is required to thaw the bacon before it is needed, but occasionally it is necessary to cook it from frozen.
Rest the bacon at room temperature for 15 minutes. This will not thaw the bacon appreciably, but it will make it easier to separate the strips.
Press a moderately stiff nylon or silicon spatula to the edges where two strips of bacon meet. Wiggle the spatula back and forth in a rocking motion while gently pressing forward. It should begin to force its way between the strips.
Continue to press and rock the spatula, until you have separated a slice of bacon from the frozen slab. Repeat until you have freed as many slices as you will need.
Place the frozen bacon in a cold heavy-bottomed skillet. Use two, for a large quantity. Turn the heat to medium and allow the bacon to cook normally until it is browned on the first side and beginning to render out its fat.
Turn the slices and brown on the second side for approximately 1 minute, or until the desired degree of crispness has been achieved. Drain on paper towels, and serve hot.
Cut the slab of frozen bacon into halves or quarters, if desired. Wrap any remaining portion and return it to the freezer.
Place the slab or portion of bacon in a cold skillet, and turn the burner to medium.
Turn the slab once the underside begins to render out some fat and become translucent, approximately 5 minutes. Once the second side has become translucent, start separating the slices of bacon with a spatula as described previously.
Transfer the separated slices to a second skillet, for the best results. Arrange the separated slices in a single layer, and fry as you normally would.
Continue separating slices until both skillets are full. Fry the bacon until both sides are well browned and the strips have reached their desired degree of doneness. Drain on paper towels, and serve hot.
The most convenient way to cook bacon from frozen is to package it in individual portions when you first bring it home from the store. Lay out the correct number of strips on a squares of waxed paper, then freeze them flat on a baking tray. Once frozen, the bacon can be stacked on its papers and placed in a zipper-seal freezer bag.