Spray the grill with oil spray and preheat the grill to medium high.
Spray the portobello mushroom caps with oil. Place the mushrooms directly on the grill for 5 minutes, then flip to grill 4 more minutes. The mushrooms should be showing some grill marks and be cooked through and tender. Remove the mushrooms from the grill and set aside to cool.
Rinse and pat dry the salmon fillet, then spread 1 tablespoon olive oil over the flesh side and sprinkle a bit of salt to taste.
Place the salmon on the grill, skin side down, after you’ve turned the mushrooms over. Grill covered for about 4 minutes, then gently turn the salmon to the flesh side. If the skin sticks to the grill, no big deal, just place the fish on a clean portion of the grill.
Grill covered for another 3 to 4 minutes. It may be cooked at this point–cut a bit in the middle of the fillet to check. You still want a bit of the dark orange color for nice, moist salmon. If you want to cook a bit more, turn over one more time and cook for a couple more minutes.
Remove the salmon to a platter when cooked to your liking. Let it rest as you prep the mushrooms.
In a medium sized bowl, combine 2 tablespoons olive oil, pomegranate molasses, thyme and garlic powder.
Dice the grilled portobello mushrooms and gently toss the mushroom pieces with the olive oil mixture. Add salt and pepper to taste.
Portion the salmon, and scoop some mushrooms to serve over the salmon. Enjoy!