In a large frying pan, over medium heat, add oil and cook potatoes until crispy. Season to taste. Remove from pan and place on a plate, set aside.
In another large frying pan, cook sausage. Do not drain grease.
Whisk eggs and ½ cup of milk together in a medium bowl and then pour into the pan that potatoes were cooked in.
Using a slotted spoon, add ½ of the cooked sausage to the eggs, along with the onions, diced green chilies, 3 cups potatoes, 2 cups cheese and biscuit pieces. Stir and cook over low flame for 3 minutes (will still be liquid).
Generously spray a bundt pan with a non stick spray.
Add ½ cup grated cheese to the bottom of bundt pan.
Pour in egg mixture and top with remaining cheese.
Pop in the oven and bake for 35-40 minutes.