Take two pieces of aluminum foil, big enough to fold around the fillet. Double them up, place spring greens on foil. Place fillet on greens and tuck greens under salmon. The greens and foil help the salmon not burn while on the grill, as well as add a little flavor as the greens cook.
Once salmon and greens are on foil, mix the slightly melted butter with garlic, salt and pepper. Spread the butter mixture over the salmon somewhat evenly. You'll want more at the thicker end of the fillet. Sprinkle the Brown Sugar over the fillet, again, more at the thicker end to get maximum flavor thru.
Slice the tomato, onion and bell pepper as thin as you can in strips. Layer the sliced vegetables over the salmon how you like. Make sure each vegetable spreads across the whole salmon.
Wrap salmon with foil and refrigerate if making early in the day, or throw on hot grill. Grill should be between 350 and 375. Let salmon cook. Prepare any side dishes if needed, throw kabobs of choice on grill if desired. Salmon should cook for at least twenty (20) minutes until you fold back foil and check if done.
When salmon is light pink in the middle, and the white fat of the fillet comes to the top it's ready to eat. Carefully pull salmon off grill. Place on platter with foil still underneath. Fold back all foil, remove vegetable if desired and sprinkle with fresh parsley.
If Grill is unavailable, you can broil in oven at 375 for the same amount of time.