Mince the garlic and finely chop the parsley. Zest the lemon, then juice it.
Melt the butter in a saucepan or skillet over low heat.
Once melted, add the minced garlic and cook until fragrant, about 1 minute (keep the heat low and don’t let it brown!). Remove from heat. Stir in the lemon juice, zest, chopped parsley, and kosher salt. Serve immediately as a drizzle for salmon, white fish, shrimp or chicken: a little goes a long way. (Store leftovers refrigerated in a sealed container and re-heat on the stovetop before serving. Note that the parsley loses its bright green color; you can add more fresh chopped parsley when you serve it.)