Portobello Mushroom Wrap

6 red onions, quartered in rings
3 oz. port wine
1½ oz. balsamic vinegar
24 bell peppers (red, yellow, green)
2 lb. large garlic cloves (skin on)
as needed, olive oil
24 portobello mushrooms, stemmed and gills removed
8 shallots, thinly sliced
12 oz. balsamic vinegar
¾ cups minced fresh chives
¾ cups minced fresh thyme
1 cup plus 2 Tbsp. minced fresh basil, divided
6 egg yolks
48 oz. mascarpone cheese
24 large spinach tortillas
1½ lb. fresh mozzarella cheese, grated
Combine onion rings (keeping them intact), port and balsamic and refrigerate overnight. The next day, drain off the marinade and grill the onions until softened.
Toss peppers and garlic with olive oil to coat and roast in a 350°F oven until pepper skins have begun to blacken and the garlic is tender. Slip garlic from the skins into food processor. Peel and seed peppers.
Combine 2 cups olive oil, the shallots, 12 oz. balsamic, the thyme, chives, and ¾ cup of the basil. Season with salt and pepper and gently toss the mixture with the mushrooms. Place the mushrooms, upside down, on a sheet pan lined with parchment or aluminum foil. Put the shallots and herbs in the mushrooms, but reserve any liquid left in the bowl. Roast until mushrooms are tender. Return them to the remaining marinade to cool slightly.
Put 6 roasted red peppers in food processor with the garlic. Add yolks and remaining 6 Tbsp. of the basil. Puree until fairly smooth, then add the mascarpone 4 oz. at a time and puree until smooth. Season to taste with salt and pepper.
For each serving to order: Warm a tortilla and spread it with 2 Tbsp. red pepper mascarpone. Slice and lay 1 mushroom on top and add several pepper strips. Top with ¼ onion, separating the rings. Sprinkle 1 oz. of mozzarella evenly over the vegetables. Melt the cheese. Slide the hot tortilla onto a plate.