Preheat oven to 350 F. and place the salmon fillet on a parchment lined cookie sheet.
Cut the top of the garlic head off, brush with oil so it doesn't burn, and place it on the baking sheet along with the salmon. Placing it in the corner of the same baking pan as the salmon is fine if there is room.
Place the pan in the oven. Note that you will have to remove the salmon before you remove the garlic. So plan accordingly.
Baking time will depend on the size of your piece of fish. But typically, times will go between 12-20 minutes. It's done when it easily flakes. Just remember that the fish will continue to cook for a bit after you remove it from the oven. So plan your baking time accordingly.
The garlic is done roasting when the cloves begin to pop out of the head.
In a blender, blend together the roasted garlic cloves and the lemon juice.
Place the fish on your plate, pour the sauce over the top, add salt to taste and enjoy.
Notes
Please note that the nutrition data below is a ballpark figure. Exact data is not possible.