Heat 2 tablespoons oil in a large pot over medium-high heat. Add onion and garlic; saute until onion is translucent, about 5 minutes. Add chicken breasts and tomato paste. Cook until chicken is well browned on all sides, about 10 minutes. Add beer; bring to a boil.
Place the remaining oil, water, bouillon, salt, pimenta, paprika, and black pepper into the chicken-beer mixture. Bring to a boil; add spaghetti. Cook until spaghetti is tender and sauce is reduced to half, about 12 minutes.