Heat olive oil in a large paella pan over medium heat.
Add diced onion and bell pepper; sauté until softened.
Stir in minced garlic and cook for 1 minute until fragrant.
Add chicken pieces; cook until browned on all sides.
Mix in diced tomatoes, saffron, and smoked paprika.
Pour in the broth and bring to a boil.
Stir in the rice and reduce heat to low; simmer for 15 minutes without stirring.
Arrange shrimp and mussels on top of the rice; cover and cook for an additional 10 minutes.
Remove from heat and let it rest for 5 minutes.
Garnish with lemon wedges before serving.