Heat 1 tablespoon oil in a large nonstick skillet over medium heat. Pat onions dry with paper towels; add to pan. Increase heat to medium-high; sauté onions 5 minutes. Add sugar and 1/2 teaspoon salt; sauté 15 minutes or until onions are tender and golden brown. Spoon into a bowl.
Heat 1 tablespoon oil in pan over medium-high heat. Add beans; sauté 8 minutes or until crisp-tender. Add onions, 1/2 teaspoon salt, and pepper; cook 2 minutes or until mixture is thoroughly heated.