Preheat the oven to 425 degrees F. (That is if you are eating right way.)
Add the leeks, garlic, and thyme, and sauté until the leeks are translucent, about another 10 minutes. Add the wine and sherry and simmer until the alcohol evaporates about 2 minutes. Transfer the mushroom mixture to a large bowl and toss it with the chicken.
NOTE: I had a lot of liquid still left in the pan and did not want to overcook the mushrooms. I drained the mushroom mixture and used the remaining liquid along with the broth to get to two cups.
Melt 9 more tablespoons of butter in the same pot over medium-low heat. Add the flour and whisk for 2 minutes. Whisk in the milk, half and half, broth, nutmeg, TJ's seasoning, and salt and pepper to taste.
NOTE: How much salt and pepper you use will be determined by how well-seasoned your chicken is, to begin with. Because I smoked mine with some pretty heavy S&P I did not need much.
Bring a large pot of salted water to a boil. Add the egg noodles and cook until tender but still firm to the bite, stirring occasionally, about 7 minutes. Drain the noodles reserving ½ c. of the pasta water. (Skip this step if you want a thicker sauce.) Add the noodles, sauce, peas, one cup of parmesan, and the pasta water to the chicken mixture. Toss until the sauce coats the pasta and the mixture is well blended.