Marinated Flank Steak with Avocado Chimichurri Sauce

Chimichurri--a South American condiment--is traditionally a combination of olive oil, vinegar, parsley, garlic salt and peppers. It has become the trendy sauce on many restaurant menus, and home cooks are discovering how much zip it can add to steaks, seafood or poultry, or as a fantastic sandwich spread. This Latin American fusion version features Hass Avocados, which add rich flavor and creamy texture.