Preheat oven to 400ºF.
In medium-sized, oven safe, lidded skillet or sauté pan, heat the olive oil to medium, then put in the onions and garlic, and sauté until the onion is translucent, stirring frequently, about 2 minutes. Add the bell pepper, tomatoes, kielbasa and fines herbs, and cook for another 2 or 3 minutes.
Pour in the rice, stir everything together, add the chicken stock and stir again. Bring the whole thing to a boil, then cover it, turn off the heat, and put into the oven. After 15 minutes, check that the rice is ready—if it's still a little undercooked, put it back in the oven, adding a dash of liquid if the whole thing is dry.
Once the rice is tender, take the pan out of the oven. Stir in the cheese (adding more if you like) and this is ready to serve.