I worked at Rubio's a longggg time ago and the chipotle lime crema (used to be called chipotle white sauce) was always my favorite. I never stole or found the recipe but I accidentally created what I feel is a strikingly similar sauce to that. I was counting my calories so I wrote everything down to track on a macro calculator and was glad I did! I didn't even look at or see other copycat recipes prior as I wasn't aiming to make that but just happened.
I haven't eaten there in a while so not sure if they still serve that sauce or if the chipotle lime crema is the same or different.
160 grams of mayo (regular tastes better than light)
80 grams of fat free Greek yogurt (yes, other recipes call for sour cream or I'm sure you could use Mexican crema but I was going for macro friendly)
Juice of 1 to 2 limes
80 grams of chipotle sauce (I'm attaching a picture of what I used and the ingredient list of it. I accidentally bought this one time instead of just the chipotle peppers in adobo and due to the spices in it, it came out better than just the chipotles in adobo)
Salt and pepper to taste
If using chipotle peppers in adobo, add some garlic powder to taste.