Preheat oven to 425°. Place bacon in a large skillet and turn heat to medium. Cook, flipping occasionally, until browned and crisp, 8-10 minutes. Transfer to a paper towel lined plate and reserve the bacon grease.
While bacon is cooking pat salmon dry with a paper towel and place on one half of a large sheet pan. In a small bowl whisk together 1 tbsp olive, maple syrup, 1 tsp lemon juice (reserve the remainder), coffee, 1/2 tsp salt, and 1/4 tsp pepper. Brush onto salmon.
Place bread cubes in a large bowl and toss together with 1 tbsp olive oil and a pinch of salt and pepper. Transfer to the sheet pan with salmon and set empty bowl aside. Bake for 7-10 minutes until salmon flakes easily with a fork. Remove bread cubes from sheet pan sooner if already toasted.
In the large bowl whisk together 1 tbsp bacon grease, 1 tbsp lemon juice, and Dijon mustard. Add apple, cabbage, arugula, toasted bread cubes, and crumbled bacon. Toss together and adjust seasoning as needed with salt and pepper. Divide salmon and Panzanella amongst plates.