For some reason when I was watching one of the Foodnetwork or Cookingchannel programs, I got “hung up on” sofrito. Almost every cuisine has their own variation on mirepoix. French, probably the best known, is a mixture of carrot, celery and onion that is lightly braised, or sweated. In Cajun cuisine, it is called the Holy Trinity and made up of onion, bell pepper and celery. It can also have garlic, parsley and a variety of other herbs in it.
The Puerto Rican sofrito, also called recaito,

Recaito is a green aromatic puree of onions, culantro (recao) leaves, garlic, green peppers and ajies dulces (small sweet chile peppers).
In Puerto Rico, recaito is used as the base seasoning known as sofrito. When preparing Puerto Rican cuisines, you may notice it called by either name.

Notice the absence of tomatoes. Typically, Puerto Ricans do not add tomatoes to their recaito. Sofrito recipes that do include tomatoes or tomato paste, sauce or juice are generally for Dominican, Cuban, Spanish, Italian, and other Mediterranean cuisines … What is Sofrito?: Simply put, sofrito is a fragrant blend of herbs and spices used throughout the Caribbean, especially Puerto Rico, Cuba and the Dominican Republic. It’s used to season countless dishes of stews, beans, rice, and occasionally meat. In most cases, it is the foundation upon which the rest of the recipe is built. Sofrito mixtures range in color from green to orange to bright red. They also range in flavor from mild to pungent to spicy.
Hundreds of recipes from the Latin Caribbean and other Latin American countries begin by instructing the cook to “make a sofrito”. It’s the first thing to go into the pot and establishes the flavor and seasoning of what’s to come. It is integral to Latin cuisine, which makes it difficult to believe that sofrito did not originate in, nor is it exclusive to Caribbean or Latin American cookery. [AboutdotCom- Latin Caribbean Food]

For more information on the history of sofrito, look at What is Sofrito?. The basic recipe for a sofrito from Recaito Puerto Rican Sofrito , is posted here.

Ingredients:
2 medium green bell or Cubanelle peppers, seeds removed
2 medium onions, peeled
1 head of garlic, peeled
1 bunch culantro leaves
6 ajies dulces (small sweet chile peppers)
Preparation:

1. Chop and blend all the ingredients in a food processor or blender.
Cook’s Notes:
Ingredients: Cubanelle Peppers are also called Italian frying peppers. Removing seeds from the ajies dulces is optional.

How to Use It: Recaito is normally used as the starting base of soups, stews, beans and rice dishes. It is first sautéed in annatto oil or lard, and then the other recipe ingredients are added. However, there are other recipes where the recaito can be added toward the end of cooking time to add a finishing touch to the recipe. [AboutdotCom- Latin Caribbean Food]

The recipe calls for culantro leaves which are like a strong cilantro. It is suggested that if you can not find these leaves to use cilantro. It will be milder. There is a lot of information here. I hope you enjoy it. Cheers!