Preheat oven to 400°. Line medium baking sheet with nonstick foil and lightly mist with spray. Wrap the bun in a separate sheet of foil to completely cover it.
In a bowl, using a fork, mix turkey, egg white, breadcrumbs, garlic, paprika, cayenne, and salt and form mixture into a patty. Place patty, bacon slices, and wrapped bun side by side on baking sheet and put in oven. Cook 10 minutes, flip bacon and patty, and cook additional 4–6 minutes until turkey is only slightly pink inside.
Remove bacon, place cheese on patty, and cook about 2 minutes until cheese is melted and patty is no longer pink inside.
Unwrap bun. Top bottom half with patty, bacon strips, lettuce, and tomato. Spread guac over underside of bun top and flip it atop the burger. Serve immediately.