Season shanks with salt and pepper to taste. Heat olive oil in roasting pan just large enough to hold shanks in single layer over medium-high heat.
Add shanks and sear on all sides, 5 to 8 minutes total. Transfer to platter. Halve or quarter mushrooms if large. Add brown and shiitake mushrooms, garlic and shallots to pan. Cook, stirring occasionally, until lightly browned, about 2 minutes.
Add stock, Port, rosemary and bay leaves. Bring to boil, scraping any bits sticking to pan. Add shanks. Cover with tight-fitting lid or foil. Bake at 350 degrees 45 minutes, then turn shanks.
Continue baking until meat is tender and just starting to loosen from bone, 45 to 75 minutes.
Set pan on counter until meat is cool enough to handle. Defat cooking juices by pouring into fat separator and
skimming top layer or by pouring juices into bowl and freezing until fat solidifies.
Pour some of sauce over shanks and arrange mushrooms on and around meat.
Serve with Hagafen Estate Bottled Napa Valley Cebernet Sauvignon and enjoy!