Cook spaghetti in a pot of salted water (add kale 3 minutes before spaghetti finish, add peas 1 minute before spaghetti finish).
In large skillet pre-heated skillet cook sausage until cooked. Remove from skillet leaving whatever grease in skillet.
In same skillet, add oil if needed, cook onions and garlic until cooked. Turn burner off.
When pasta and vegetables are cooked, remove from pot and put directly into skillet with onions and garglic. Save pasta water in pot.
In heat proof bowl mix eggs, white miso and a pinch of salt and pepper until blended. Add about a ladle (1/4 cup) hot pasta water into bowl of egg mixture, put bowl over hot pasta water pot and keep whisking.
Add meat back into skillet with onion, pasta and vegetables.
Pour egg mixture and chili flakes (if using) into skillet and toss to combine.
Add more pasta water to make sauce, to taste. Salt and pepper as needed.