Heat the grill over medium-high heat and follow the same for stovetop grill pan.
In a little bowl, mix the lemon zest, minced garlic, chopped thyme, olive oil, salt, chopped rosemary,and pepper to prepare the marinade.
To dry the salmon belly, pat it with paper towel then place it skin-side down on a plate or shallow dish. Pour the marinade over the salmon by ensuring that it covers the salmon evenly. Allow it to soak in the marinade for around 15-30 minutes at room temperature or an hour in the fridge for better taste.
Once the grill is hot, put some oil on the grates to avoid sticking the fish. Now, put the salmon belly on the grill with the skin facing down and cook for 4-5 minutes without moving it. It makes the skin delicious and crispy.
With a help of spatula, gently turn the salmon belly and grill for an another 3-4 minutes until the meat is opaque and flakes easily with a help of fork. Avoid overcooking, as it may become dry.
After cooking the salmon belly, remove it from the grill and put it on a plate. You can garnish it with parsley and serve hot with lemon slices on the side.
It’s time to serve the salmon belly with your favorite side dishes like rice, salad, or steamed vegetables etc.