Preheat oven to 375°F, and coat baking sheet with cooking spray.
Blend pistachios in blender or food processor until finely chopped. Set aside.
Add sun-dried tomatoes, roasted red peppers, and garlic to blender or food processor (no need to rinse), and purée until smooth.
Spray 1 side of each eggplant slice with cooking spray, and place sprayed-side down on baking sheet. Spread 2 Tbs. sun-dried tomato mixture on each eggplant slice, and sprinkle with 1 Tbs. ground pistachios. Bake 15 to 20 minutes, or until eggplant is tender and pistachio topping is browned and crispy.