Coat non-stick sauté pan with cooking spray. Heat pan to medium heat. Season salmon fillet with salt and pepper and place in pan. Sear salmon for 4-5 minutes per side, until golden brown on the outside and flaky on the inside. Remove from pan a cool at room temperature.
Wash and dry spinach, blueberries, and tomatoes and place in large bowl. sprinkle walnuts on top of salad.
To make dressing whisk ingredients in a small bowl or shake in a mason jar. Season with salt and pepper to taste.
Pour dressing over salad and rest salmon fillet on top. Enjoy!