Add 1 cup of the chicken stock, vermouth, and 4 tablespoons of butter to a medium-sized sauce pot and cook over medium heat until it is reduced to about 1/3 cup. It will be almost like a syrup.
Whisk in the heavy whipping cream until combined and set aside. Add the noodles or pasta to a large pot of boiling salted water and cook for 7-8 minutes or until they are al dente or slightly less.
Add the remaining 2 tablespoons of butter to a large rondeau or Dutch oven pot over low to medium heat and cook the onions for 10 to 15 minutes or until they turn very light brown.