A family member was admiring a picture of my oyster mushrooms, up to 8″ across, and asked if they were too big to eat. Not if you like to grill. I love a plateful of giant oyster mushrooms, as long as they were still fresh and moist and not dried out when picked. The big ones have leathery bases and need to have the stem (technically a stipe) trimmed off to the extent that a little semi-circle is taken out of the base.
Now the toughest part is gone. Clean the rest and rub it on both sides with basic steak marinade. Make sure that the marinade gets up in the gills, since this helps keep them moist while cooking. Sprinkle the gill side with a good smoked salt.
Heat the grill to about 300 degrees and sear nicely on the upper side. Turn and cook on the gill side until done, turning them 90 degrees midway if you want nice crosshatched sear marks. Meanwhile, preheat the broiler. Put the caps on a baking sheet lined with parchment paper, gill side down. Sprinkle lavishly with grated Parmesan, making sure to sprinkle the areas of bare parchment paper to make the lacy garnish. Broil, turning the pan as necessary, until the cheese is just beginning to brown. Eat.
The argument could be made that there’s no point in fussing with crosshatched grill marks since they’re on the bottom and don’t show. This is a fair point, but in good spring weather it’s a pleasure to fuss a bit at the grill.
This is a good meal to share with vegetarians if you don’t use any fish sauce in the marinade. In my opinion the final cheese crusting adds a lot to the flavor and so it isn’t ideal for vegans, but try it if you feel so inclined. If you don’t have oyster mushrooms try portobellos, which come alive with some seasoning. If you find really big meaty fresh shiitakes, they are ideal for grilling whole. If you’re lucky enough to find some porcinis in the woods or market in the fall, they are superb sliced thickly and grilled.