A good tartar sauce should be piquant and powerful. It is much better made at home—where you can guarantee its potency—than purchased. Here’s one. Tartar sauce 1 cup homemade mayonnaise 1/3 cup chopped cornichons 3 tablespoons chopped capers 3 tablespoons roughly chopped parsley leaves 1 tablespoon lemon juice 1 tablespoon white wine vinegar optional: 1 tablespoon olive oil a single drop hot sauce salt Mix everything lightly into the mayonnaise, only whisking in the optional olive oil if the sauce threatens to get thin. Taste for salt.