1 lb extra-large shrimp (21 to 25), peeled and deveined
¾ lb squid, sliced into rings (optional)
8 to 9 medium garlic cloves, minced or pressed through a garlic press (more if including the squid)
1 lb boneless, skinless chicken thighs, each thigh trimmed of excess fat and halved crosswise
Roasted red bell pepper (enough to equal one large pepper)
12 oz marinated artichoke hearts (optional)
8 oz Spanish chorizo, sliced ½ inch thick on the bias
1 medium onion, chopped fine (about 1 cup)
1 can (14 ½ oz) diced tomatoes, drained, minced, and drained again
2 cups Bomba, Valencia, or Arborio rice
3 cups low-sodium chicken broth
⅓ cup dry white wine, such as Sauvigon Blanc
½ teaspoon saffron threads, crumbled
1 bay leaf
1 dozen mussels, scrubbed and debearded
½ cup frozen peas, thawed
2 tsp chopped, fresh parsley
1 lemon, cut into wedges, for serving
Adjust oven rack to lower-middle position; heat oven to 350 degrees. Toss shrimp, ¼ teaspoon salt, ¼ teaspoon black pepper, 1 tablespoon oil, and 1 teaspoon garlic in medium bowl; cover with plastic and refrigerate until needed. Do same with squid rings if using. Slice peppers and set aside.
Add 1 teaspoon oil to Dutch oven; heat oil until shimmering but not smoking. Add chicken pieces in single layer; cook, without moving pieces, until browned, about 3 minutes. Turn pieces and brown on second side, about 3 minutes longer; transfer chicken to medium bowl. Reduce heat to medium and add chorizo to pot; cook, stirring frequently, until deeply browned and fat begins to render, 4 to 5 minutes. Transfer chorizo to bowl with chicken and set aside.
Add enough oil to fat in Dutch oven to equal 2 tablespoons; heat over medium heat until shimmering but not smoking. Add onion and cook, stirring frequently, until softened, about 3 minutes; stir in remaining garlic and cook until fragrant, about 1 minute. Stir in tomatoes; cook until mixture begins to darken and thicken slightly, about 3 minutes. Stir in rice and cook until grains are well coated with tomato mixture, 1 to 2 minutes. Stir in chicken broth, wine, saffron, bay leaf, and ½ teaspoon salt. Return chicken and chorizo to pot, increase heat to medium-high and bring to boil, uncovered, stirring occasionally. Cover pot and transfer to oven; cook until rice absorbs almost all liquid, about 15 minutes. Remove pot from oven. Uncover pot; bury artichoke hearts (if using) into rice. Scatter shrimp and squid rings (if using) over rice, insert mussels hinged side down into top layer of rice (so they stand upright), arrange bell pepper strips in a pinwheel pattern, and scatter peas over top. Cover and return to oven; cook until shrimp are opaque and mussels have opened, 10 to 12 minutes.
Let paella stand, covered, about 5 minutes. Discard any mussels that have not opened and bay leaf, if it can be easily removed. Sprinkle with parsley and serve, passing lemon wedges separately.