Leftover brisket makes for a twist on the classic sloppy joe, a deliciously messy sandwich that's as kid-friendly as it is appealing to adults.
In a skillet, heat oil over medium. Add onion and cook until softened, 3 to 4 minutes. Add tomato paste; stir 1 minute. Add pureed tomatoes, sugar, vinegar, Worcestershire sauce, and 1 cup water. Simmer 10 minutes. Add brisket; toss to heat through. Serve on toasted buns, with sliced red onion and cilantro.