Heat half of the olive oil in a large frying pan over medium-high heat. Add turkey bacon, cooking slices for 4 to 5 minutes per side. Remove from heat. Add remaining olive oil and then add mushrooms, sautéing until just cooked.
Meanwhile, toast buns. Add turkey bacon, slice of tomato, mushroom slices, red onion, arugula and mayo in between each bun. Serve and enjoy.