Cut the whole chiles in strips and open to remove all seeds by rinsing each in running cold water. Beat the eggs; add the milk, flour, and pepper; blend to mix.
Layer the chiles and grated cheese into a 7 x 11 greased pan or other similar flat casserole. (I use my Corningware flat oblong one.) Pour the milk mixture over the layered chiles and cheese.
Bake in 325 degree oven for 40-45 minutes or until knife inserted comes out clean. Top should be light brown.