Coat the bottom of a medium skillet with cooking spray and place over medium heat. Add the diced onion and garlic; cook and stir until the onions are soft and translucent. Reduce the heat to medium-low and mix in the green chiles; cook for 1 minute. Stir in the cream cheese until fully melted. Remove the skillet from the heat.
Place the Cheddar, hominy, and cream cheese mixture in a 2 quart casserole; stir until well combined.
Bake in preheated oven for 35 minutes. Cool for 5 minutes before serving.
