Combine the paprika, garlic powder, salt, onion, cumin, oregano, black pepper, red pepper flakes, and optional saffron and cayenne pepper in a small bowl.
Pat the chicken thighs dry with a paper towel and add to a separate medium bowl. Drizzle it with 2 Tablespoons of olive oil and half of the seasoning. Toss to coat both sides well with the seasoning.
Add another Tablespoon of olive oil to the bottom of a deep skillet, like a cast-iron skillet, over medium-high heat. Once the oil is hot and shimmering, add the chicken thighs smooth-side-down and sear for 3-4 minutes without moving. Flip and cook for another 1-2 minutes. The chicken should be deeply golden brown, but it does not need to be cooked all the way through. Transfer it to a clean plate or cutting board.
Drizzle the last Tablespoon of olive oil into the bottom of the skillet over medium heat. Add the shallot and cook for 3-4 minutes, until soft. Add the garlic and cook for another minute, until fragrant.
Stir in the uncooked rice and remaining spice mixture and cook for 1-2 minutes to combine and toast the rice.
Pour in the white wine and chicken broth and use a spatula to scrape any brown bits from the bottom. Stir in the fire-roasted tomatoes, squeeze of lemon juice, and frozen peas, and stir to combine.
Bring the mixture to a boil over medium-high heat and add the partially cooked chicken on top of the rice. Cover, turn it down to low, and simmer for 20-25 minutes until the rice is fluffy and the chicken reaches an internal temperature of 165°F. Check the rice 1-2 times briefly while it’s cooking to ensure it’s not burning the bottom of the pan and adjust the heat lower as needed.
Top with fresh chopped parsley, a squeeze of lemon juice, flaky salt, or toasted pine nuts.