Soak wood chips in enough water to cover for 1 hour. Drain. Place 10-inch cast-iron skillet on one side of grill to preheat. Fill smoker tray with wet wood chips. Place smoker tray on grill rack on other side of grill. Close lid.
Heat grill on high heat about 10 minutes or until smoke appears from chips. Reduce heat to medium. Place tomatoes on grill rack. Close lid. Smoke tomatoes for 5 minutes. Remove from grill. Reserve 12 tomato wedges. Coarsely chop remaining tomatoes.
Increase heat to high. Add chorizo to preheated skillet; cook and stir 3 minutes or until lightly browned. Remove from skillet. Set aside. Add chicken; cook and stir 3 minutes or until lightly browned. Add onion and bell pepper; cook and stir 3 minutes. Add serrano pepper, garlic and chopped smoked tomatoes; cook and stir 2 minutes. Add smoked paprika, rosemary, salt and pepper.
Stir in rice, stock and reserved chorizo until well mixed. Place smoked tomato wedges on top of rice mixture. Using pot holders, carefully cover pan tightly with foil. (Pan will be very hot.) Reduce heat to low. Close lid. Cook 30 minutes or until rice is tender and all of the stock has been absorbed. Sprinkle with parsley. Using pot holders, carefully remove pan from grill.