This is a creamy jalapeño salsa.
El Regio and El Pollo Rico in Austin, Texas are two Monterrey (that's Nuevo León, México Monterrey) style rotisserie chicken places. They serve this krazy good green sauce there. Theirs is just boiled jalapeños blended with oil and some salt, but mine has a couple of extra ingredients.
Here is my version: (makes a little over 1 cup):
1 clove garlic
1 tbs or so lime juice
1/2 cup or so oil (light tasting oil*)
1/2 tsp salt or to taste
Put jalapeños in a pot of water and boil for about 20 minutes until they are soft. Remove them from the water. Stick the clove of garlic in the hot water for a few minutes, then remove it. This is a trick to take the sharp edge off of the garlic by cooking it very slightly. Allow your jalapeños to cool completely, then using gloves, remove the stems and seeds with your hands.
Add all off the ingredients except oil to a blender. Turn on blender and grind jalapeños for a moment, then slowly drizzle in the oil till you have a beautiful green emulsification.
This sauce thickens a bit once you refrigerate it, so don't make it too thick to start out with. It should still be a bit liquidy when you take it out of the fridge, not a solid.
OPTION: Alternatively, roast your jalapaños under a broiler/on the stove/on the grill. Allow to cool and remove the stems, seeds, and most of the skin. Use the charred jalapeños and proceed with the rest of the recipe. This yields a slightly smoky green sauce flecked with black charred bits for color. It's very delicious.
*I like sunflower oil for this. I am sure El Regio and El Pollo Rico use soybean oil. For heart healthy oils, a light olive oil works, too. But avoid a strongly flavored olive oil or it will be overpowering in the salsa and give it a strange undertaste.