In a large zip-top bag combine:
1/2 cup lower-sodium soy sauce
2 tablespoons fresh lemon juice
2 tablespoons ketchup
2 tablespoons brown sugar
1 tablespoon Worcestershire sauce
3/4 teaspoon crushed red pepper flakes
1 tablespoon crushed garlic
Add and mix well:
2 pounds pork tenderloin, trimmed and cut in 2 inch pieces or 2 pounds boneless chicken thighs
Seal bag and refrigerate at least 1 hour.
Preheat charcoal grill.
Remove pork from bag and discard marinade.
Skewer pork or chicken onto 8 6-inch skewers.
Grill about 3 minutes per side.
Serve with brown rice and grilled vegetables. You could easily add grated fresh ginger and sesame oil for a more Asian flavor.