- Trim the beans.
- In a large saucepan, toss in your beans and cover with water. Bring to heat and boil for 10 minutes. They should turn somewhat tender.
- Bring a large skillet to medium heat and melt the butter. Add in the flour plus the salt and pepper for seasoning whilst stirring.
- Eventually, blend in the chicken broth. Allow to boil for a few minutes whilst stirring. It should thicken. Take off from heat.
- Now, in a small bowl, blend in the milk with the egg yolks. Pour a little bit of the hot broth mixture into the egg mixture. Pour this back into the pan while stirring thoroughly.
- Bring this to boil and stir for a few minutes. It should turn thick. Toss in the parsley. Eliminate water from the beans and serve with the sauce!