Set oven to 350. Spray 9x13 pan with cooking spray (I line mine with foil as well).
Crumble hamburger into large bowl. Add rest of ingredients (except tomato sauce). Lightly mix all together. Mold into a rounded heap.
Slide out into middle of 9x13 pan. Shape into a roughly oval shape. Pour tomato sauce over top, trying to keep as much on top as possible.
Bake at 350 for 1 hour, until crusty, and sauce looks somewhat dry (not shiny). Take out and let rest for 10 minutes. (I fold papertowels and place on sides of pan to absorb grease, during the 10 min., making sure to remove before cutting and serving.)
Take advantage of ovens heat to bake or roast potatos to go along with meatloaf.