Preheat the oven to 350°F (175°C).

Grease a baking dish and spread the hash browns in an even layer at the bottom.

In a skillet, cook the sausage and onion over medium heat until browned and crumbled, about 8-10 minutes. Stir in the kale and cook until wilted, about 2-3 minutes. Remove from heat and set aside.

In a separate bowl, whisk together the eggs, milk, onion powder, garlic powder, and a generous pinch of salt and pepper.

Pour the egg mixture over the hash browns. Top with half of the cheese. Spread the sausage mixture evenly over the cheese, then sprinkle the remaining cheese on top.

Cover the dish with aluminum foil and bake for 50 minutes. Remove the foil and bake for an additional 10 minutes, or until the cheese is golden and a knife inserted in the center comes out clean.

Let sit for 5 minutes before serving.