4 lg. Bermuda onions, thinly sliced
2 qt. milk
1 tsp. whole mace
1 c. butter
1 tbsp. salt
2 egg yolks
Finely chopped parsley
Croutons

Put onions, milk, mace, butter, and salt into a large saucepan. Bring to boiling, then reduce heat, and cook over low heat until onions are very tender, about 30 minutes. Remove and discard mace. Beat egg yolks, adding a small amount of the hot mixture while beating. Stir egg mixture into soup and cook 1-2 minutes, or until slightly thickened. Sprinkle servings with parsley and top with croutons.