To prepare broth, pour boiling water over tea bag in a large saucepan; steep 5 minutes. Remove and reserve tea bag. Bring tea mixture to a boil. Add miso, stirring with a whisk until blended. Add mushrooms; bring to a boil. Reduce heat, and simmer 5 minutes. Remove from heat; cover and set aside.
To prepare filling, cut open reserved tea bag, and pour out loose tea; chop, if needed. Combine loose tea, minced onions, and next 8 ingredients (minced onions through garlic) in a medium bowl. Working with 1 won ton wrapper at a time (cover remaining wrappers with a damp towel to keep them from drying), spoon 1 tablespoon shrimp mixture on half of each wrapper. Moisten edges of wrapper with water; bring 2 opposite corners together. Pinch edges together to seal, forming a triangle.
Bring reserved tea mixture to a boil; add won tons, gently stir, and cook 4 minutes or until won tons float to the top. Ladle 5 won tons and 1 cup broth into each of 4 bowls. Divide bell pepper and onion slices evenly among bowls. Serve immediately.
Note: Ground turkey may be substituted for the ground pork.