Vegetarian Portobello French Dip Sandwich - cooking recipe

Ingredients

Mushroom Essence
1/2 lb whole mushrooms or 1/2 lb mushroom stems
6 garlic cloves, lightly crushed
1 1/2 tablespoons tamari
French Dip Spread
1/2 teaspoon olive oil
1 small shallot, minced
1/2 teaspoon minced garlic
1 tablespoon chopped fresh herbs (basil, thyme, parsley or chives) or 1 teaspoon dried herbs (basil, thyme, parsley or chives)
2 tablespoons white wine
1/4 lb unsalted butter (1 stick) or 1/4 lb vegan margarine, at room temperature (1 stick)
salt & freshly ground black pepper
The Sandwich
3 tablespoons olive oil
2 teaspoons minced garlic
3 portabella mushrooms (reserve stems for au jus)
salt & freshly ground black pepper
1 large yellow onion, halved and sliced thinly
1 rustic baguette
4 4 slices mozzarella cheese (optional) or 4 slices provolone cheese (optional)

Preparation

Mushroom Essence: Combine the mushrooms, garlic, and 6 cups of water in a 3 quart saucepan. Bring to a boil, then lower the heat and simmer for about 1 1/2 hours, until the liquid has been reduced to 1 1/2 - 2 cups.
Strain the liquid and add the tamari. Keep warm if using immediately, or refrigerate/freeze.
French Dip Spread: Heat the olive oil in a small skillet over medium heat. Add the shallot, garlic, and herbs and cook for two minutes, stirring as you go. Add the wine and cook until mostly evaporated, but still moist. Remove from the heat and cool to room temperature. Add the cooled shallot mixture to the softened butter and mix well. Add salt and pepper to taste. Makes 1/2 cup.
The Sandwich: Preheat the oven to 350\u00b0F Mix 2 tbsp of the olive oil and the garlic together in a small bowl. Brush mixture on both sides of the portobello caps, and sprinkle with salt and pepper. Place them gill sides down on a baking sheet, and roast for 25 minutes.
When the mushrooms are cool enough to handle, slice each cap thinly at an angle, about 8-10 slices per cap.
While the portobello caps are in the oven, heat the remaining 1 tbsp oil in a pan over medium heat. Add the onion and cook for about 5 minutes, until it begins to soften. Turn the heat to low and cook the onion for 15-20 minutes, stirring occasionally. If it begins to stick, add 1-2 tbsp of sherry or water to the pan.
Cut the baguette into 4 equal portions 5-6 inches long, avoiding the rounded ends. Slice each in half lengthwise. Spread each of the 8 halves with 1 tbsp of the French Dip Spread. Heat a large skillet over medium heat. Place as many of the halves that will fit, spread-side down, for 3 minutes. Repeat for all the halves.
Place 4 baguette bottom-halves, griddled side up, on a baking sheet lined with parchment paper. Top each with 1/4 of the sliced mushrooms and grilled onions. Top with cheese.
Place in the 350\u00b0F oven for about 10 minutes, until heated through and cheese melts. Top with the remaining halves and bake for 3 minutes more.
Slice each sandwich in half at an angle and serve with about 1/3 cup of Mushroom Essence.