Bake for 1 hour, or until cooked through.
Surprise Ideas:

Vegetables: Add chopped carrots, celery, or spinach to the meatloaf mixture.
Cheese: Stuff the center of the meatloaf with shredded cheese, such as cheddar or mozzarella.
Hard-boiled eggs: Peel and slice hard-boiled eggs and place them in the center of the meatloaf before baking.
Bacon: Wrap bacon around the outside of the meatloaf before baking.
Tips:

For a richer flavor, use a combination of ground beef and ground pork.
Add your favorite seasonings to the meatloaf mixture, such as garlic powder, onion powder, or Italian seasoning.
Top the meatloaf with ketchup or barbecue sauce before baking.