Place a large skillet over medium heat and coat with nonstick cooking spray. In a medium bowl, whisk together eggs, milk, and salt.
Add eggs to hot pan and scramble. Once cooked, remove from pan.
Using the same pan, add ground turkey and taco seasoning. Use a wooden spoon to break up meat into small pieces. Add chopped onions and continue to cook and stir until meat is cooked.
Drain and rinse black beans and add to the pan. Drain the tomatoes and add to pan; stir and heat through.
Add in chopped spinach and cooked eggs. Stir to combine and remove the pan from the heat.
Warm tortillas in the microwave so they're easy to roll and sprinkle with shredded cheese. Place a small amount of filling along the center and roll into burritos. Serve warm!