Spread the bread slices out on a rimmed baking sheet and let them sit until dried out, about 4-6 hours.
Preheat the oven to 375 degrees F.
Line a 12-1/2x9-1/2-inch rimmed baking sheet with parchment paper.
In a bowl, add the tomatoes, the oil, the salt, and the pepper and toss to combine.
Spread the tomatoes over the prepared baking sheet, but to one side.
Arrange the bacon strips as close to an even layer as possible on the other side of the prepared baking sheet.
Roast the tomatoes and the bacon until the tomatoes are wrinkled and begin to soften and the bacon is about 3/4 of the way cooked, about 20-25 minutes.
Transfer the tomatoes and the bacon to a plate and turn off the oven.
Discard the fat and the parchment paper from the baking sheet.
Wash the baking sheet, then coat it with the extra oil.
In a bowl, add the eggs, the milk, the salt, and the pepper and whisk to combine.
Dip the bread slices, one at a time, into the egg mixture and turn to coat them.
Place the coated bread slices in shingled, overlapping layers on the prepared baking sheet.
Evenly pour the remaining egg mixture over the top of the coated bread slices. It will pool at the top, sink through the bottom, and then absorb as it sits.
Sprinkle the coated bread slices with the parsley and the cheese.
Top the cheese layer with the tomatoes and the bacon.
Refrigerate the coated bread slices, covered, for at least 1 hour and up to 24 hours.
Preheat the oven to 375 degrees F.
Bake the breakfast bake, uncovered, for 15 minutes.
Reduce the heat to 350 degrees F and bake until the breakfast bake is puffed and cooked through, about 20-25 minutes.
Let the breakfast bake cool slightly.
Serve the breakfast bake garnished with the cilantro.