Tater Tot Breakfast Casserole

1 small onion, diced
1/2 each poblano pepper and red bell pepper, diced
1 Tbsp butter
1/2 tsp cumin
1/2 tsp ancho chile powder
1/4 tsp garlic powder
16 ozs tater tots
3/4 c shredded pepper jack cheese
12 eggs, beaten
1/2 c milk
1/2 tsp salt
1/4 tsp pepper

Bake covered at 375° for 25-30 minutes, then uncovered another 5 minutes or until browned on top