Bring a large pot of water to a boil and season generously with sea salt. Add the egg noodles and cook according to the package directions until al dente. Drain, then toss the noodles with 1 tablespoon of butter and a pinch more sea salt to taste. Set aside and keep warm.

Heat 2 tablespoons of butter in a large skillet over medium heat. Add the cremini mushrooms and a pinch of sea salt, then cook, stirring occasionally, until the mushrooms are browned and have released their moisture, about 8-10 minutes. Remove the mushrooms from the skillet and set aside.

In the same skillet, add the sliced onion and crushed garlic. Cook over medium heat until the onions are tender and translucent, about 5 minutes. Stir occasionally, scraping up any browned bits left from the mushrooms for extra flavor.

Pour in the dry white wine to deglaze the pan, scraping up any stuck bits from the bottom. Let the wine simmer until it reduces slightly, about 2 minutes. Meanwhile, whisk the flour into the mushroom broth until smooth. Add this mixture to the skillet along with the reserved browned mushrooms (from Step 2), thyme sprigs, dijon mustard, and smoked paprika. Simmer gently until the sauce thickens, about 5-7 minutes.

Remove a few tablespoons of the hot sauce and mix it with the sour cream or Greek yogurt to temper it. Stir the mixture back into the skillet; this helps prevent curdling. Let the sauce gently heat through. Season with sea salt and freshly ground black pepper to taste. I always like to taste and adjust the seasoning at this point—the earthiness of the mushrooms really shines when you balance the salt just right.

To serve, spoon the creamy mushroom sauce over the buttered noodles (from Step 1) on individual plates or a large serving dish. Garnish generously with finely chopped fresh parsley or chives for a burst of color and freshness.