Cut onion into strips. Mice the garlic. Over medium flame, heat oil in a large pot and add the onion and garlic. Cook stirring until onions are translucent. Be careful not to brown them. Next cut peppers into strips, carrots into slices and add to the onions. Add about a cup of the stock and bring to a boil. Reduce heat all the way to low, cover the pot and let everything simmer for about an hour or until very soft. Cut chicken into cubes and season to preference. In a separate pot cook chicken on cooking spray. Add to the vegetable stew and add the rest of the stock if it seems dry. Cut up tomatoes into cubes, add along with the tomato sauce into the chicken/vegetable mixture. Season with paprika. Add salt and pepper to taste. Let everything simmer for another 30 minutes or so. Mix cornstarch with water and add to the mixture. Let it come to a boil. Serve!