In skillet combine squash and potatoes. Add 1 cup water. Bring to boiling, reduce heat. Simmer, covered, 8 to 10 minutes or until vegetables are tender. Drain. Set aside. In same skillet cook sweet pepper, onion, and garlic in hot olive oil over medium heat until onion is tender, stirring occasionally. Stir in brown sugar. Remove from heat. Stir in thyme, basil, 1/2 tsp. salt, and peppers.
Combine sweet pepper and potato mixtures in skillet. Place spinach in bowl. Top with potato mixture Sprinkle thyme. (Or, let potato mixture stand at room temperature, covered, up to 2 hours before serving over spinach.) Makes 8 to 10 (1-cup) servings