Heat the olive oil in a large Dutch oven over medium-high heat. Sprinkle the chicken with salt and pepper. Add 3 drumsticks and 3 thighs to the Dutch oven and cook until browned on both sides, 7 to 8 minutes. Remove the chicken pieces with a slotted spoon and set aside. Repeat with the remaining drumsticks and thighs.
Add the onions and peppers to the pot and cook until the onions are translucent, 2 to 3 minutes. Add the garlic and saute for about 1 minute. Add the paprika, cumin, saffron and bay leaves, stirring until incorporated. Next, add the diced tomatoes, chicken broth, beer, rice and 1 teaspoon salt; mix well. Bring to a boil, then lower to a simmer.
Return the chicken pieces to the pot, cover, and transfer to the oven for 20 minutes. Remove the pot from the oven, add the peas and pimientos, then cover and return to the oven until the rice is completely tender, another 5 to 10 minutes.