Preheat oven to 375°F. Prepare a large piece of aluminum foil on a rimmed baking sheet.
In a small bowl, mash together the softened 4 tablespoon unsalted butter, 2 cloves garlic, minced 1 teaspoon flat parsley, 1 teaspoon Dijon mustard, 1/2 teaspoon coarse Kosher salt, 1/2 teaspoon ground black pepper, 1/2 teaspoon lemon juice and 1/4 teaspoon lemon zest.
Slather, best you can, all over the 1 pound salmon fillet (cut into pieces or whole). Don't worry about it being even, after it melts it will evenly distribute.
Wrap salmon tightly and bake for 15-20 minutes. This depends greatly on the thickness of your salmon.
Remove salmon and pull back aluminum foil. Allow to rest for 3-4 minutes before serving.
If you've tried this recipe, come back and let us know how it was in the comments or ratings!