Preheat oven to 375 degrees, when ready, put cubed pieces of cheese in a cast iron skillet and place it in the oven.
Prepare the topping by spraying a second cast iron skillet (or pan) with non-stick spray, add chopped onion and cook for 3-4 minutes. Stir in chopped dates and garlic, then cook an additional 7-8 minutes. Add chipotle sauce, season with salt and pepper to taste; add a little water if dry. Pour the topping over the melted cheese in the first skillet and place it back in the oven until completely melted and the cheese is a little brown and crunchy, approximately 5 more minutes. Serve with warm corn or flour tortillas.