Preheat oven to 350 degrees and spray a 9" deep dish pie plate with cooking spray and set aside.
In a large skillet melt butter over medium-high heat. When hot, add hash browns and leave until nicely browned. You may peek, but if they are not golden brown do not flip them. When ready, flip the potatoes and brown the other side. Remove from heat and let cool. When cool enough to handle, press the hash browns into the bottom and sides of a pie dish to form the crust.
Then, crack 1 egg into a medium-sized mixing bowl and whisk together with flour until completely smooth. Add remaining 8 eggs and whisk until smooth then stir in milk or half-and-half, ham, onion, poblano pepper, salt and pepper.
Pour egg mixture into crust and top with shredded cheese. Place in oven and bake for 28–30 minutes or until light golden brown on top and firm in center. Remove from oven and allow it to cool for at least 10 minutes before slicing and serving.
Notes
Have leftovers? Quiche has a second, even tastier life come day two!