How to Make It
Preheat oven to 375°F. Evenly coat a rimmed baking sheet with 1 tablespoon of the olive oil. While oven preheats, place chorizo and chicken in a single layer on baking sheet, and cook 10 minutes or until oven is preheated.
Add onion, bell pepper, garlic, paprika, and half of the salt and pepper to chicken mixture; toss to coat. Return to oven, and bake 10 minutes, stirring halfway through.
Add rice to baking sheet, and toss to coat. Spread mixture in an even layer, and cook 10 minutes. While rice cooks, Stir together chicken stock, seafood stock, and saffron in a large measuring cup; microwave 2 minutes.
Gently stir stock mixture, tomatoes, and wine into rice mixture until well combined; carefully return to oven, and bake 20 minutes.
Increase oven temperature to 425°F. Remove baking sheet from oven, and drizzle up to 1/4 cup water over rice if all liquid is absorbed. Sprinkle peas over the top; slightly nestle shrimp into rice mixture. Spread mussels evenly over top. Drizzle paella with remaining olive oil, and sprinkle with remaining with salt and pepper. Bake at 425°F until mussels have opened, 6 to 8 minutes.
Cut 1 lemon in half, and squeeze juice over paella. Cut remaining lemon in 8 wedges. Sprinkle with parsley; serve with lemon wedges.