Preheat oven to 325°F.
Place walnuts on a baking sheet and transfer to the oven to toast them up, about 10-12 minutes (your nose will know when they are done).
In a medium-size skillet over medium heat, melt 1 tablespoon of butter with the EVOO. Add the onions and cook until tender, about 2-3 minutes.
Add mushrooms and garlic, and brown, about 4 minutes.
Add the spaghetti and toast until golden brown, about 5 minutes. Season with salt and ground black pepper then stir in the white wine. Stir continuously as it absorbs then add in a ladleful of stock. Keep stirring as that absorbs. Continue the process until the spaghetti is tender and cooked through.