Sofrito is the base for most Puerto Rican dishes, and this one is better than store bought (difficult to find in the stores in the Western United States). This can be added to beans, rice, soups, stews, you name it.
Recao is a popular Caribbean herb with many aliases. Among them, culantro, long coriander, ngo-gai, and Mexican coriander. It may possibly be found in Latin grocery stores, or substitute with cilantro.
Aji Dulce is a common ingredient in Puerto Rican recipes. It is a small, sweet red pepper. If you can't find it, use red bell pepper.