Preheat oven to 350ºF. Spray a 9x13" dish with cookng spray, set aside.
Drain cans of green chilies. Take a strip of cheese and insert it into each chili. Place in prepared baking dish.
When all chilies have been filled with cheese and are inside the baking dish, mix together eggs, milk, flour and baking powder in a mixing bowl. Beat with a whisk until thoroughly combined and smooth.
Pour egg mixture over chilies and then top with cheese.
Place in preheated oven and bake for 30 minutes, until the egg is puffy and the cheese is bubbly. Slice into squares and serve. Enjoy!