Rinse rice until water runs clear.
Heat olive oil over low heat; add scallion, garlic, parsley, thyme, seasoning peppers, black pepper, and scotch bonnet. Sauté gently for about 3 minutes.
Add grated carrot and continue cooking 2–3 minutes.
Stir in rice, salt, and vegetable stock; sprinkle saffron if using.
Bring to a boil, then reduce heat; cover and simmer 20–25 minutes until liquid is absorbed.
Turn off heat, remove scotch bonnet, cover, and let rest 10 minutes.
Fluff with fork, garnish with extra parsley, and serve.