Marinated Tomatoes With Onions

Ingredients

• 1 1/2 teaspoons basil
• 1 teaspoon sugar
• 1/2 teaspoon salt
• 1/4 teaspoon dry mustard
• 1/4 teaspoon garlic powder
• 1/4 teaspoon pepper
• 3 tablespoons balsamic vinegar
• 1/2 cup oil
• 1 large white onion, thinly sliced
• 3 large tomatoes, thinly sliced
• 1/4 cup chopped parsley