Preheat oven to 400 degrees.
Sauté the diced red pepper, carrots, and onions in butter for 5-10 minutes over medium heat until softened. Allow to cool.
Meanwhile in a large bowl add ground beef, cottage cheese, bread crumbs, seasoning and eggs.
Add the cooled cooked veggies.
Use your hands to combine the mixture really well. Use 1/4 cup to measure out mixture and form into balls.
You should have about 20 medium size meatballs. Place on a rimmed greased cookie sheet.
Bake at 400 for 30-40 minutes until cooked through.
For the sauce combine ketchup, sugar, and mustard in a saucepan and simmer until the sugar is melted about 5 minutes.
Serve the meatballs with the sauce or ketchup.
