Brown ground beef in a large skillet over medium-high heat. Season with onion powder and garlic powder while cooking. Cook until fully done and drain grease.
Transfer seasoned beef to slow cooker.
Add tomato paste, ketchup, beef broth, brown sugar, Dijon mustard, Worcestershire sauce, chili powder, apple cider vinegar, salt, and pepper. Stir until well combined.
Cover and cook on low for 3 hours, stirring once halfway through
Taste and adjust seasonings as needed.
Serve on hamburger buns.
Notes
Pro Tip: Don't skip browning the ground beef first! This step adds so much more depth of flavor than just throwing raw meat into the slow cooker. Also, stirring half way through helps prevent the sauce from sticking and ensures even cooking. This is a great way to get that perfect sloppy joe meat texture every time.