In a large skillet melt margarine or butter. Remove from heat. Stir in Parmesan cheese and garlic powder. Add bread cubes, stirring until cubes are coated with margarine mixture. Spread cubes in a single layer in a shallow baking pan. Bake in a 300 degrees F oven for 10 minutes; stir.
Continue baking about 5 minutes more or until bread cubes are dry and crisp. Cool completely before using. Transfer to a serving bowl and serve as a salad accompaniment. Makes about 2 cups (12 servings).
Prepare croutons up to 1 week before serving. Store tightly covered.