Instant Pot Instructions 

1. Heat oil on “sauté” function.  Add onion, garlic, mushrooms, salt and pepper and saute 7-9 minutes or until mushrooms release their liquid.
2. Sprinkle with the flour, and give a stir coating the mushrooms. Add the sherry wine,  2 cups broth, and mustard and stir well, scraping up any browned bits  (to prevent the burn error).
3. Add the pasta, and stir.
4. Set instant pot to pressure cook on high for 3-4 minutes. (see notes)
5. Manually release (placing a towel over the steam).
6. Stir in the sour cream, and keep on warm setting for 5-10 minutes. The sauce will thicken slightly but will remain “saucy” enough for dipping garlic bread. Taste, add more mustard if you like.
7. Sometimes for extra depth, I’ll add a teaspoon of soy sauce in at the end, up to you.

Stovetop Instructions. 

1. Boil the pasta, according to the package in salted water until al dente. Drain.
2. Make the Sauce: Heat oil in a large skillet over medium heat. Saute onion, garlic and mushrooms until mushrooms release all of their liquid and this liquid cooks off, about 10 minutes. Add the wine, cook it off again. Stir in 1 heaping tablespoon flour, and cook 1 minute. Add the broth, salt, pepper and mustard (start with 1 tablespoon) scraping up any browned bits, and stir to incorporate well, letting it simmer and thicken.
3. Stir in the cooked drained pasta and sour cream. Taste, adjust salt and mustard adding more if you like.