Preheat your oven to 400 degrees F and spray a large baking dish with a non-stick spray. Set aside.
In a heavy-bottom saucepan, add the butter and melt over medium heat. Whisk in the flour and cook until it turns a golden brown color. Very slowly, pour in the beer. Be careful, as beer is known to bubble over. Continue to whisk for 2-3 minutes and then whisk in the green chile. Bring to a low boil and reduce the heat to a simmer, continuing to whisk until the sauce has thickened substantially, about 10 minutes. With the heat still set on low, stir in the sour cream, cream cheese, garlic powder and a dash of salt and pepper. Stir until smooth and creamy. Adjust seasoning to taste and remove from heat. Set aside.
Assemble your enchiladas, by placing a tortilla on a flat surface. Add a couple tablespoons of chicken, a couple tablespoons of cheese, and a tablespoon of black beans. Roll the enchilada up tightly and place, seam side down, into the prepared pan. Repeat this step for the rest of the tortillas, making sure you have about 1/2 cup of cheese left over for topping later on.
Top the enchiladas with the green chile sauce and the remaining cheese.
Bake the enchiladas for 20-25 minutes or until melty, bubbly and slightly brown. Remove from heat and let stand for 2-3 minutes.
While your enchiladas are baking, prepare you salsa. In a small bowl, combine the pomegranate arils, red onion, cilantro, jalapeno, lime juice, sugar and a dash of salt. Mix carefully as to not break up the pomegranate arils. Set aside.
Serve your enchiladas by topping with pomegranate salsa, avocado and cilantro. Enjoy immediately!