Blend the red bell pepper, half of the onion, and chopped tomatoes until smooth. Set aside.
Heat oil in a large pot. Finely chop the remaining half onion and sauté until soft.
Add tomato paste and fry for 2–3 minutes until dark red.
Pour in the blended pepper mixture. Simmer for 10–15 minutes, stirring occasionally, until thickened and the oil begins to separate.
Stir in curry powder, thyme, paprika, salt, white pepper (if using), and the Maggi cube.
Pour in chicken stock and bring to a boil.
Rinse the rice well and add it to the pot. Stir once, cover tightly with foil or a lid.
Reduce heat to low and let cook undisturbed for 25–30 minutes.
Once rice is tender and liquid is absorbed, fluff gently. Let rest, covered, for another 5–10 minutes before serving.