in a small heavy saucepan combine syrup, water, mustard, garlic, and salt
and simmer until reduced to about 1/2 cup
cool
heat broiler
arrange salmon, skin-side down, on oiled rack of broiler pan
and season with salt
broil salmon 4 inches from heat source, 6 minutes
brush with sauce and broil until just cooked through, about 4 minutes
more
note:
To insure even cooking, buy salmon cuts from the middle of the fillet, not the narrow tail end. When portions are the same thickness, they cook evenly.