Don't skip over this excellent antipasto because of the anchovy paste; only the cook will know it's there. There's no fishy taste at all, just exceptionally flavorful mushrooms and a bright, lemony tang.
In a large glass or stainless-steel bowl, using a fork, stir together the lemon juice, anchovy paste, salt, and pepper. Stir in the oil. Add the mushrooms and parsley and toss.
Quick From Scratch Italian