Make It
Step 1
Heat medium saucepan over medium heat; add butter and oil. Add onion; cook, stirring frequently, until it becomes transparent. Add flour; stir well to form a paste.
Step 2
Add milk, stirring well so mixture doesn't get lumpy, and cook for 5 minutes. Add cream cheese, stirring well to melt. Stir in Oaxaca cheese and then Jack cheese. Mix until melted.
Step 3
Add Media Crema and mix well. Season if desired. Mix in cooked shells. Serve immediately.