In a large skillet, add a little canola or vegetable oil and the onions on medium heat. Heat through. Add the ground beef and cook the beef until done. Once the beef is cooked add the tomato soup, water and pizza seasoning. Reduce the heat to low and simmer. While the beef and sauce are simmering, preheat the oven on broil and spread the butter evenly on each English muffin half. Sprinkle with garlic salt and top each muffin half with 4 slices of pepperoni. Pop the muffins under the broiler on a cookie sheet for about 2 minutes or until they just begin to brown on the edges. Take them out of the oven and top each English muffin with 1/4 cup of the meat and sauce mixture. Top each of those with the cheese. Place back under the broiler for another 2 to 3 minutes or until the cheese turns golden brown and starts to bubble. Enjoy!