In a large pot, boil water. Add whole wheat spaghetti and cook until al dente. Keep 1 cup of pasta water to use later; drain the rest.
In a large saucepan at medium heat, combine olive oil and garlic. Stir to evenly cook until garlic is lightly golden brown; approximately 3-5 minutes.
Add ham and cook, stirring continuously, for 1-2 minutes. Next, add green beans, black pepper, onion powder and dried basil leaves. Stir until well incorporated.
Cover and let green beans cook at low heat for 5-7 minutes. Stir occasionally to avoid garlic and ham from burning.
Next, add Dijon mustard, Swiss cheese, and the ½ cup of reserved pasta water. Cook and continue tossing until the mixture has thickened into a sauce; approximately 1-2 minutes.
Add in cooked spaghetti and toss until well incorporated. Toss in chopped parsley.
Serve into 4 bowls. Spoon any remaining sauce over spaghetti noodles.