Pepperoni Chili

1 lb lean ground beef
3/4 cup chopped onion
1 (26 ounce) jar three cheese spaghetti sauce
1 1/2 cups water
2 teaspoons sugar
1 (14.5 ounce) can diced tomatoes
1 (4 ounce) can sliced mushrooms
2 ounces sliced pepperoni (I put in way more, like 5-6 oz, and I use the little mini pepperonis because they are cool)
1 tablespoon beef bouillon
1 tablespoon chili powder
1 (14.5 ounce) can kidney beans, drained and rinsed
1 cup shredded Cheddar cheese

Crumble ground beef into a large stock pot over medium-high heat. Add onions, and cook, stirring, until beef is evenly browned. Drain grease, if necessary.
Pour in the spaghetti sauce, water, sugar, tomatoes, mushrooms, pepperoni, bouillon, chili powder and kidney beans. Bring to a boil. Reduce heat, and simmer uncovered for 30 minutes, stirring occasionally, to blend flavors.

Source: http://allrecipes.com/recipe/italian-style-chili/