Pat thawed turkey breast with paper towels to absorb excess moisture.

In a small bowl, whisk together paprika, garlic powder, onion powder, salt and pepper. Rub mixture on the outside of the turkey breast and place in a slow cooker sprayed with nonstick cooking spray.

Place sliced onion on top. Cover and cook on low for 5-6 hours or until it reaches an internal temperature of 165 degrees F.

Cut into slices and serve.