Rub the cleaned large intestines with rock salt and lemon and rinse thoroughly with plenty of water. Turn them inside out so the inner surface faces outward and rinse once more, then drain.

Heat the oil in a pan and sauté the chopped onions, add the tomato and pepper paste and stir until fragrant. Add the washed rice, red pepper flakes, black pepper, allspice, and salt and sauté for 3 minutes, then let cool slightly.

Loosely stuff the filling into the intestine casing, accounting for the rice's expansion. Tie off at intervals or knot the ends with kitchen string to close. Important: Do not stuff tightly, or it will burst while cooking.

In a large pot, drop the mumbar into boiling water seasoned with a spoonful of tomato paste and salt. Simmer over low heat for about 45 minutes until the rice inside softens. Pierce the boiled mumbar in a few places with a needle.

Heat the oil in a pan and fry the boiled mumbar until browned on all sides. Caution: Make sure the filling and the casing are completely cooked through. Slice and serve hot.