This easy casserole, full of ground beef, roasted broccoli and topped with hash browns, was inspired by the classic Minnesota Tater Tot hotdish. Roasting the broccoli before adding it to the casserole gives the whole dish a much more complex and exciting flavor, but it's by no means necessary. If you want to keep it simple, skip roasting the broccoli (Step 2) and use 6 cups frozen broccoli, thawed, in its place (omit 1 tablespoon oil, as well).