How to Make It
Coarsely chop enough anchovies (about 10 fillets) to equal about 3 tablespoons, and measure 4 teaspoons oil from tin. Reserve any remaining anchovies and oil for another use.
Heat chopped anchovies, anchovy oil, garlic, and crushed red pepper in a small skillet over low. Cook, using the rounded side of a spoon to smash anchovy mixture until it resembles a paste, about 4 minutes.
Remove from heat, and transfer to a small heatproof bowl. Stir in parsley, lemon zest and juice, and olive oil, adding more lemon zest and juice to taste. Serve warm or at room temperature as a spread on toast, a dip for crudités, or a condiment for steak.