Prepare the Canner and Jars
Prepare your pressure canner according to the manufacturer's directions. Wash and inspect seven quart jars and keep them hot until you're ready to fill them.
Brown the Ground Beef
Brown the ground beef, breaking it into small pieces as it cooks. Work in batches if necessary.
Drain the excess fat well and transfer the meat to a large stockpot.
Cook the Vegetables
Add the chopped onions and bell peppers to the ground beef. Cook until the vegetables begin to soften.
Make the Homemade Sloppy Joe Sauce
Add the ketchup, tomato sauce, water, Worcestershire sauce, brown sugar, apple cider vinegar, prepared mustard and black pepper.
Stir well and bring the sloppy joe mixture to a boil.
Reduce the heat and simmer uncovered for 20 to 30 minutes, stirring frequently to prevent scorching.
The sauce should be thick enough to cling to the ground beef but still moist and easily ladled. Don't reduce it until it becomes dry or paste-like. The goal is a sloppy joe filling that will be ready to heat and serve once the jar is opened.
Filling the Jars
Ladle the hot sloppy joe filling into hot quart jars, distributing the meat and sauce evenly.
Leave 1 inch of headspace. Remove air bubbles and check the headspace again.
Wipe the jar rims, center the lids and apply the bands fingertip tight. Place each filled jar into your prepared pressure canner.
Pressure Canning Sloppy Joes
Vent the pressure canner with a steady stream of steam for 10 minutes before pressurizing it, following the directions for your particular canner.
Process quart jars for 90 minutes.