1. In a saucepan melt the butter and fry the onion and garlic. Reserve.
2. In the same butter cook the rice over medium heat, stirring constantly. Add boiling water to cover; add carrots and tomatoes. Cook over moderate heat until the water is absorbed. Cover and simmer over low heat.
3. In a frying pan heat the butter and fry the chorizo, chilies and cabbage. Once cooked add the reserved garlic-onion mixture. Stir to blend.
4. Grease a baking dish and place a layer of rice in the bottom, then the rest of the ingredients.