Heat oven to 200ºF.
Combine the pork, scallions, bell pepper, egg, ketchup, mustard, Worcestershire, brown sugar, salt, pepper, and cayenne in a medium mixing bowl and stir until well combined. Set aside.
To form the dumplings, remove 1 wonton wrapper from the package, covering the others with a damp cloth. Brush 2 of the edges of the wrapper lightly with water. Place 1/2 rounded teaspoon of the pork mixture in the center of the wrapper. Fold over, seal edges, and shape as desired. Set on a sheet pan and cover with a damp cloth. Repeat procedure until all of the filling is gone.
Heat 1 tablespoon of oil in a 10-inch sauté panover medium heat, just until smoking. Add 10 to 12 potstickers to the pan and sauté until golden, 1 to 1 1/2 minutes per side. Gently add 1/4 cup of hot broth per pan of wontons, cover, and cook until liquid evaporates, approximately 2 minutes. Remove wontons to a heatproof platter and place in warm oven. Wipe the pan of any excess liquid or debris and repeat until all wontons are cooked. Serve immediately.