Preheat oven to 475.
Combine ingredients in mixing bowl. Toss to combine.
Spread onions evenly on a pan.
Bake until golden brown, tossing every 10 minutes for 30 minutes.
Add salt to water and boil.
Add beans, blanch for 8 minutes.
Put in ice bath and drain.
Melt butter in a skillet.
Add salt and pepper and stir for 4-5 minutes.
Add garlic and nutmeg, cook for 1-2 minutes.
Sprinkle flour in the pan and stir, cook for 1 minute.
Add half and half, cook for 6-8 minutes.
Stir in beans and onions.
Bake at 400 for 15 min.