Place the dried porcini mushroom in a small bowl and cover with 1 cup of hot (not boiling) water. Let sit 15 minutes.
Heat a little water or broth in a medium sauce pan on medium high heat, and saute the shallots until well browned and caramelized, about 5 minutes. Add more broth or water a little at a time as needed to keep things from sticking. Reduce the heat to medium, add garlic, and saute 2 more minutes.
If using the optional sliced mushrooms, add them to the pan now with a little more water or broth and saute them on medium high heat about 5-8 minutes or until well browned.
Add the 1/2 cup of the wine (or the vinegar) to the pan, and deglaze (loosen up any brown bits) from the pan. Add the vegetable broth to the pan and simmer on medium high heat until the gravy reduces and begins to thicken, about 15 minutes.
While the gravy is reducing, remove the porcini mushrooms from the bowl, reserving the liquid. Give them a gentler squeeze to release excess liquid. Chop the porcinis into a small dice and set aside.
Using a large spoon or small ladle, remove the reserved liquid 1 spoonful at a time into another small bowl or measuring cup, being careful to leave the sediment at the bottom of the bowl behind. (Or strain using a coffee filter.) Add the miso and flour to the reserved liquid, and whisk together until the miso and flour are dissolved.
When the gravy is finished reducing, add the diced diced porcinis, reserved liquid/miso/flour mixture and thyme to the pan, and simmer on medium low heat 5 more minutes.
Add the final 1/4 cup of red wine, and simmer 1-2 minutes to allow the alcohol to cook off. (See notes.)
Servings. Makes about 2 cups. Serving size (for nutritional information) is 1/3 cup--or 1/6th of recipe. (Actual results may vary, based on how much you reduce your gravy.)
The miso paste acts as a healthy salt and thickener in this recipe. If you're allergic to soy, you may be able to find chickpea, brown rice or another type of miso.
To thicken your gravy, if you don’t want to add flour, simply reduce the gravy longer until it reaches the desired consistency.
About Shallots. I kept the shallots in the background so that this gravy has mass appeal (including kids), but it you love onions and what more of a mushroom-onion type of gravy, by all means double or triple the amount in the recipe. Just keep the dice small.
Cooking with wine is completely optional, but it lends a rich, acidic note to sauces that frankly takes them to the next level. In this recipe, I like to add some wine at the very end of cooking to enhance the wine flavor, but you can simply add it with the rest of the wine earlier in the recipe if you prefer.
For a mellower flavor, add a splash or 2 of plant milk just before serving. This gravy has quite an intense mushroom flavor, and the milk will tone that down some if needed.
To make your gravy perfectly smooth, process in a blender or use an immersion blender
To make your gravy richer and creamier, soak some cashews in hot water for 15 minutes, drain, add to a blender with just enough liquid to get it to blend, then stir some of this 'cashew cream' into the gravy.