Combine brown sugar and steak seasoning. Add sugar mixture to the skillet and stir to combine.
When the meat has browned, add in onion, red pepper, vinegar and Worcestershire sauce to the skillet. Reduce heat to medium and cook for 5 minutes.
Add tomato sauce and paste to pan. Stir to combine. Reduce heat to simmer and cook for 5 minutes longer.
Spoon sloppy joe meat onto bun bottoms and cover with bun tops.