Pour the 14.5 oz can of chicken broth into a small saucepan. Bring to a simmer over medium heat and cook until reduced to 3/4 cup. Set aside and keep warm.

Drain the 14.5 oz can of diced tomatoes in a colander; set the drained tomatoes aside (you may reserve the juice if you like).

Peel and cut the small onion into pieces about 1 inch square.

Core and cut the two red bell peppers into pieces about 1 inch square.

Trim any visible fat from the three chicken breasts and cut them into about 1-inch cubes.

Season the chicken cubes with 1 teaspoon sweet paprika, salt, and fresh-ground black pepper to taste. Mix to coat.

Heat 1 tablespoon olive oil in a large non-stick frying pan over medium-high heat. Add the seasoned chicken in a single layer and cook, turning as needed, until the pieces are nicely browned on all sides and barely cooked through, about 5 minutes. Transfer the chicken to a plate and reserve any juices.

Add the remaining 2 teaspoons olive oil to the same pan. Add the onion and cook, stirring occasionally, until softened, about 4 minutes.

Add the remaining 3 teaspoons sweet paprika, 1 teaspoon hot paprika, and 1/2 teaspoon ground caraway seed (if using). Cook, stirring, about 1 minute to bloom the spices.

Add the red bell peppers and cook until they begin to soften when pierced with a fork, about 3–4 minutes.

Add the drained diced tomatoes and cook about 2 minutes.

Pour in the reduced chicken broth (3/4 cup) and bring to a gentle simmer. Cook 2–3 minutes, until the liquid is hot and bubbling.

Return the browned chicken and any accumulated juices from the plate to the pan. Reduce heat to low and simmer just until the chicken is heated through, about 2–3 minutes.

Turn off the heat and let the skillet sit 1–2 minutes so it stops simmering (this prevents the sour cream from curdling).

Temper the sour cream: scoop out 2–3 tablespoons of the hot liquid from the pan into a small bowl, stir that into the 1 cup sour cream until smooth, then add the sour cream mixture back into the skillet and stir gently to combine. Do not allow the sauce to boil after adding the sour cream.

Serve hot (as a stew or over rice or cauliflower rice, if you prefer). Store leftovers in the refrigerator for a few days; reheat gently over low heat (do not boil).