Preheat the oven to 350°F.
In a large pot of boiling salted water, blanch the asparagus pieces for 2-3 minutes until bright green and slightly tender. Drain and set aside.
In a large mixing bowl, combine the cooked rice, cheddar cheese, mozzarella cheese, sour cream, cream of mushroom soup, garlic powder, onion powder, salt, and pepper. Mix until well combined.
Add the blanched asparagus to the mixture and stir gently to coat the asparagus evenly.
Transfer the mixture to a greased 9x13-inch baking dish, spreading it out evenly.
In a small bowl, combine the crushed crackers with the melted butter, mixing until the crackers are evenly coated. Sprinkle the cracker mixture over the top of the casserole.
Bake in the preheated oven for 25-30 minutes, or until the casserole is bubbly and the top is golden brown.
Let the casserole cool for about 5 minutes before serving.