Add the canned tomatoes with their juices, red bell pepper, half of the onion, and the Scotch bonnet or habanero, if using, to a blender. Blend until completely smooth. For less heat, remove the chile seeds first or leave out the chile.

Heat the oil in a large, heavy pot or Dutch oven over medium heat. Finely chop the remaining onion and cook it in the oil until softened and lightly golden, about 4 to 5 minutes.

Stir in the tomato paste and cook, stirring often, until it darkens slightly and smells sweet rather than raw, about 2 minutes.

Carefully pour in the blended tomato mixture. Cook uncovered over medium heat, stirring often, until the sauce has thickened, the oil begins to rise around the edges, and the raw tomato smell has cooked away, about 12 to 15 minutes.

Stir in the stock, thyme, curry powder, smoked paprika, salt, black pepper, and bay leaves. Bring the sauce to a gentle boil and taste carefully, adding a little more salt if needed.

Stir in the rinsed rice until it is evenly coated. Reduce the heat to very low, cover the pot tightly, and cook until the rice is tender and most of the liquid is absorbed, about 25 to 30 minutes. Avoid stirring while it cooks. If the pot looks dry before the rice is tender, add a small splash of hot stock or water around the edges.

Remove the pot from the heat and let it stand, covered, for 10 minutes. Remove the bay leaves and gently fluff the rice with a fork before serving.