Fill a medium sized pan 3/4 full of water and bring to a boil. Season with kosher salt.
Slice 1/2 lb mini cremini mushrooms in half and chop 1/3 cup walnuts and set aside until ready to use.
Melt 2 tbsp unsalted butter in a medium sized skillet over medium high heat and add sliced mushrooms. Sauté mushrooms until they have released most of their juice, grate and add 1 clove garlic and stir to combine. Cook for another minute or until the garlic becomes fragrant. Add chopped walnuts and stir to combine, cook for 3-4 minutes or until the walnuts are toasted.
Add 1/4 cup chicken stock and deglaze the pan scraping up any brown bits. Season with kosher salt and freshly ground black pepper
Add 2 handfulls fresh baby spinach and stir to combine. Cook until the spinach has wilted, 2-3 minutes.
When the water is boiling, add frozen ravioli and cook until the ravioli floats to the surface, about 3-5 minutes.
Using a slotted spoon, trasfer ravioli to the mushroom mixture and add 2 tbsp crème fraîsche or rich sour cream. Stir to combine. When fully combined, spoon a generous portion into individual serving bowls.
