In a medium saucepan, cook the bacon over medium-high heat until brown and crisp. Drain the bacon and reserve, discarding the bacon drippings (or saving for another use). In the same saucepan, add the cranberries, lemon juice, and brown sugar. Cook over medium-high heat until the cranberries begin to burst, stirring often. Reduce the heat to medium-low and continue to cook until thickened. Stir in the savory and reserved bacon at the end.
In a large sauté pan, heat the oil over medium heat. Slice the ciabatta rolls in half and place each half in the hot oil, cut-side down. Cook for a few minutes until the bread is golden and crisp (work in batches if needed). To assemble, spread a generous amount of cranberry-bacon jam on the bottom half of the roll and Dijon mustard on the top half. Place a few slices of turkey on the jam (I like to heat it up first). Next, layer the sliced tomatoes on top of the turkey, seasoning with salt and pepper. In a small mixing bowl, add the watercress and season to taste with lemon juice, olive oil, salt, and pepper. Top the tomatoes with the seasoned watercress and close the sandwich. Cut in half and enjoy!