Super Easy Pizza Burgers

I remember having these for hot lunch when I was in grade school.  I found 2 recipes that I combined together to come up with this super easy meal.  My family inhaled it.  There was not any left.  I am going to double it next time and see if I can freeze them.  They were so easy and tasted just like I remember.
 
Hope you enjoy!
 
 
Super Easy Pizza Burgers
5 Hamburger buns
1 lb hamburger
1 (8oz) can tomato sauce
1 tsp oregano
1 cup shredded mozzarella cheese

Brown hamburger and drain grease.  Add tomato sauce and oregano; mix well.  Spoon onto 1/2 of a hamburger bun and place on cookie sheet.  Sprinkle with cheese and cook at 350 degree for 10 minutes.