1 large eggplant (about 1 1/4 pounds), cut crosswise into 8 slices
1/4 teaspoon salt
1/2 cup low-fat mayonnaise
5 tablespoons fat-free milk
2 tablespoons Dijon mustard
2 teaspoons chopped fresh or 1/2 teaspoon dried rosemary
1 teaspoon fresh lemon juice
2 garlic cloves, minced
2 cups trimmed arugula
2 green tomatoes, each cut into 4 slices
8 (1-ounce) slices sourdough bread
1/4 cup (1 ounce) crumbled goat cheese
Sprinkle both sides of each eggplant slice with salt. Place eggplant slices on paper towels; let stand 20 minutes. Blot dry with paper towels.
Combine mayonnaise and next 5 ingredients (mayonnaise through garlic) in a medium bowl. Remove 1/4 cup mayonnaise mixture; set aside. Add arugula to mayonnaise mixture in bowl; toss gently.
Coat both sides of the eggplant slices with cooking spray. Place on grill rack, and grill 5 minutes on each side or until lightly browned. Transfer eggplant to a plate. Coat both sides of tomato slices with cooking spray. Place tomato slices and bread slices on grill rack; grill 2 minutes on each side or until tomato is tender and bread is lightly browned.
Place 1 bread slice on each of 4 plates. Top each slice with 1/3 cup arugula mixture, 2 eggplant slices, 2 tomato slices, and 1 tablespoon goat cheese. Drizzle 1 tablespoon reserved mayonnaise mixture over each serving. Top with remaining bread slices.