Step 1

In a large sauce pan melt butter over medium heat. Add in onion, and peppers. Cook for 5-7 minutes or until softened.

Step 2

Add garlic and cook for another minute.

Step 3

Whisk in flour and cook for around 30 seconds.

Step 4

Pour in milk and cook for 5 minutes whisking constantly until thickened.

Step 5

Stir in tomatoes and cilantro.

Step 6

Turn the heat down to low. Add cheese 1/4 a cup at a time. Let cheese melt before stirring in more. Repeat until all cheese is used up.

Step 7

Stir in sour cream and salt to taste.