Preheat oven to 350°F and lightly grease a 7x11-inch baking dish with butter or nonstick spray. Set aside.
In a medium bowl, whisk together the eggs, evaporated milk, garlic powder, onion powder, and salt.
Whisk in flour until smooth.
Stir in cheeses and green chiles, then pour mixture into the prepared baking dish.
Top with sliced jalapenos, then bake until very lightly browned around the edges, 25-30 minutes.
