The bright flavors of fresh parsley and garlic make this vibrant sauce a favorite accompaniment to Argentine beef.
Stir together vinegar, water, garlic, bay leaf, salt, red pepper flakes, and black pepper until salt is dissolved.
Whisk in oil until combined, then whisk in parsley. Let stand for 30 minutes at room temperature. Discard bay leaf and stir sauce before serving.
By Matt Rodigheri