In a medium bowl, combine 1/2 cup softened unsalted butter, 4 minced garlic cloves, 8 anchovies packed in oil, drained and minced, 1/2 teaspoon hot paprika, 1/2 teaspoon fresh lemon juice, and kosher salt to taste. Mix with a fork until smooth and spread on steak. Or transfer to waxed paper, roll into a cylinder, chill, and slice.