For the stock
In a saucepan over high heat, add the olive oil and sauté the onion until tender. Add the garlic and continue sautéing. Add the wine and add the stock. Simmer, smoldering for about 45 minutes. Drain from fine dining pan, cool quickly and refrigerate.
*The mushrooms needed for this recipe will probably not be enough to produce the amount of stock needed. You may make up the difference with more stems, whole button mushrooms or, more fried mushrooms