Preheat the oven to 375ºF. Combine the turkey, carrots, red pepper, parsley, egg and bread in a medium bowl. In a small bowl mix together the ketchup and chili powder. Add half the ketchup-chili mixture to the meat. Season with a dash of salt and few grounds of pepper. Mixt well with a wooden spoon or your hands.
Form the meat mixture in a loaf shape and place in a baking pan only slightly larger than the loaf. You can smooth the edges with a spoon but don’t worry too much about making it perfect. Spread the remaining ketchup-chili sauce over the top of the loaf.
Bake for 40 minutes. Remove from the oven, lay the cheese slices over the top and pile on the caramelized onions (instructions below). Return to the oven for another 15 minutes. Let stand for about 10 minutes before serving.
The most efficient way to make this dish is to have the onions sliced and ready to go in the pan before you assemble the meatloaf. Don’t try to cook them while you are assembling the meatloaf though because they need frequent attention and if you’re anything like me two tasks at once is one too many. When the meatloaf goes in the oven melt the butter in a shallow pan over medium-high heat. Add the onions and cook, stirring often for about 10 minutes or until the onions begin to brown.
Turn the heat down to medium and continue to cook for another 20 minutes. Stir frequently, scraping the browned bits from the bottom of the pan. If it seems like the onions are burning turn the heat down. You can even add a tablespoon of water if you need to. The idea is to cook these onions slowly so they caramelize and not to brown them too quickly. After 20 minutes the onions should be complete wilted and have turned a deep golden brown. Now is when you add the brown sugar and balsamic vinegar. Stir well, turn the heat down a bit more and cook for another 10 minutes. Don’t forget to stir and scrape frequently. When the onions are done follow the instructions above to finish off the meatloaf.