Remove husks from the tomatillos.
Rinse and place in a stock pot.
Add the jalapenos, garlic, and onion.
Cover with water and bring to a boil.
Simmer for 5 minutes.
Discard water and remove the ingredients.
Place in a blender along with lime juice, cilantro, and salt.
Blend until smooth.
Heat oil in a stock pot.
Slowly, add the tomatillo sauce, or it might splatter.
Cover and simmer on low to medium heat for 15 minutes.
Let cool slightly.
In the blender, add 1 cup of the sour cream and ½ cup of the cooled tomatillo sauce.
Blend.
Add the cream sauce to the tomatillo sauce.
Mix well.
Then add the remaining sour cream.
Mix together and set aside.
Reserve 1 cup of the sauce for serving.