I had this at a Food City store when they were doing a demo for the cheese and loved it so much I figured out the recipe. So easy and so good! Not too hot but wonderful flavor. I serve it with Tostitos or other good tortilla chips.
Rinse the Poblano chiles and place them under the broiler to roast. You may also roast them on the stove but this is easier. Turn periodically with tongs until all sides are roasted but not blackened. Remove the chiles and place them in a plastic bag to "sweat" for easier removal of the seeds and outer skin. I choose large dark green chiles. You can also make the dip with other chiles such as Anaheim (often used for chile rellenos) but it will change the flavor of the dip.
While the chiles are roasting mix the sour cream and the crumbled Cotija cheese in a large bowl. Cotija cheese has a taste somewhat between Parmesan and Feta cheese but is quite mild.
Chop the prepared chiles and mix them in with the sour cream-cheese mixture. I like to leave them in the refrigerator for 30 minutes or so in order to let the flavors meld but it is not critical. Serve with your favorite chips and enjoy! The mildness of the sour cream and the cheese makes this a mellow dip even with the chiles. I never have left overs, but they may be stored for an additional day in the refrigerator in a covered container if desired.