Remove the top and insides of the peppers and place in a baking dish with enough room for all peppers to stand up. Brown hamburger then add seasonings and half of your onions. Prepare Rice a Roni in a skillet, add butter to deep skillet and add the rice. Stir frequently until rice is a golden brown. Slowly add your water and seasoning mix from the box. Then add your can of tomatoes and rest of your onions. Bring to a boil then cover and simmer about 20 mins until rice is tender. Then add your hamburger and shredded cheese *save a little to sprinkle on top* Mix until cheese has melted. Spoon your spanish rice mixture into each pepper until full. Cover peppers and cook at 400 degrees for 25 mins. Uncover and cook an additional 15 mins. Once there done sprinkle a little cheese on top and allow to melt.