Heat a medium skillet over medium high heat. Add oil, onion, garlic, peppers. Saute peppers, stirring frequently, 5 minutes. Add asparagus and corn, cook 3 to 5 minutes longer. Add beans and heat them through, 1 or 2 minutes. Season dish with salt and pepper, to your taste, then stir in parsley. Transfer to dinner plates or bowls and serve.