Inspired by George Graham here.

Preheat the oven to 350ºF.

3 cups long-grain white rice, such as Supreme
3 cups chicken stock
1 package Paellero paella seasoning with saffron or any commercial paella seasoning

1 large yellow onion, diced
1 cup thinly sliced green bell pepper
3 tablespoons minced garlic
2 tablespoons olive oil
4 ounces Spanish chorizo, finely chopped
1 (12-ounce) can tomatoes, diced
1 bay leaf
1/2 cup dry white wine
Chicken stock, if needed

In a rice cooker or pot with a tight-fitting lid, add the rice, chicken stock, and seasoning. Stir to combine and cook on low heat until the rice is fully cooked. Keep warm.

In a large pan or Dutch oven over medium-high heat, sauté the onion, pepper, and garlic in olive oil until the onions turn translucent. Add the chorizo and sauté for another five minutes. Add the tomatoes, bay leaf, and white wine and cook for 10 minutes. If the sofrito seems dry, add some chicken stock.

Combine the cooked rice and sofrito in a baking dish or paella pan and cover with a tight lid or aluminum foil.
Preheat the oven to 350ºF. Place in the oven until heated through, about 20 minutes.

Keep warm until serving.