Cook green beans to desired doneness as directed on bag. Drain; cover to keep warm.
Meanwhile, in 12-inch nonstick skillet, melt butter over medium-high heat. Cook bell pepper and garlic in butter 2 to 4 minutes, stirring constantly, until bell pepper is crisp-tender. Stir in walnuts; cook until hot.
Add green beans; sprinkle with seasoned salt. Cook and stir just until thoroughly heated. Spoon into serving dish.