Shred cheese (about 6-1/3 cups); reserve 6 Tbsp separately for garnish.
Saut‚ onion in oil until soft, about 5 minutes.
Stir in green chiles and next 2 ingredients.
Stir in milk and next 2 ingredients; cook over medium heat, stirring constantly, until smooth.
Reduce heat to low; stir in 6 cups cheese. Stir until cheese thoroughly incorporates. Do not boil.
Stir in cilantro.
PER ORDER
Heat, but do not boil, 1-1/2 cups soup; garnish with tortilla strips and 1/2 Tbsp cheese.
Recipe courtesy of the California Milk Advisory Board.