Pre heat the oven to 350°F/176°C. In a mixing bowl big enough to handle all of the ingredients, plus some room for mixing, whisk the egg. Add the oats, onion, bell pepper, and salt. Mix it all together.
Then add the beef and the pineapple and thoroughly mix everything together. Spray oil a 9"x 5" loaf pan, add the mixture and pat it down.
Bake for 35 to 40 minutes. It should be 155-160°F/71°C on a meat thermometer. Slice it up and top with the gravy or sauce of your choice. We went with our our Marinara Sauce tonight, but, you can use any topping you want. Gammy says that her grandma would use BBQ sauce or sometimes a can of Cambells's cream of mushroom soup, not diluted, just right out of the can and heated up.