Wash all of the produce before starting.
Peel the heads of garlic and place them in a blender. You don’t need to cut or crush the individual bulbs, just make sure they are fully peeled.
Peel and quarter the onions and add those to the blender as well.
Next, cut the green bell peppers in half and remove the seeds from them. Cut them in half again and then add them to the blender as well.
Blend the ingredients on high speed for a minute or until the ingredients start to break down. Then add one bunch of cilantro and blend for another minute or two until the cilantro is incorporated.
Add the second bunch of cilantro and blend again, and then add the parsley. Let the sofrito blend until all of the ingredients are broken down and fully incorporated.
You may need to stop the blender to scrape down the sides with a spatula in order to fully blend the ingredients.
Store the sofrito in the refrigerator or freeze it. I recommend freezing in small portions, such as one or two tablespoons or a quarter cup, so that it’s easier to pull out of the freezer for use in recipes!
