Spray a baking dish with cooking spray. Add the chicken breasts. Add the mushrooms, sun-dried tomatoes, mayo, and salt on top of the chicken. Mix together.
Bake for 30 min or until the chicken is 160 degrees when checked with a meat thermometer.
I start temping my chicken breasts around the 20-minute mark. I temp every five minutes until they hit 145 degrees and then every 3 minutes. As soon as they are 160 I remove from the oven and let them rest.