Start by cleaning the squid thoroughly under running water. Remove the ink sac, beak, and internal parts, then cut into uniform 1-inch rings. Pat them dry with paper towels.
Mix vinegar, salt, garlic, and cracked peppercorns in a bowl. Add the squid rings to this mixture and let them marinate for exactly 15 minutes – no longer, or the vinegar will start cooking the squid.
While the squid marinates, heat oil in a large pot over medium-high heat (350°F/175°C). Fry the potato cubes until golden brown, about 5-7 minutes. Remove them and set aside.
Using the same pot, lower the heat to medium and sauté the chopped onions until they become soft and clear, about 4-5 minutes. Add the garlic and peppercorns from the squid marinade and cook for another minute until fragrant.
Add the marinated squid to the pot and stir for just one minute. Pour in the remaining marinade and cook for another minute, stirring gently.
Pour in the tomato sauce and add the sliced bell peppers. Let it come to a boil, then lower the heat to medium-low (300°F/150°C). Add the fresh chilies and let everything simmer for 5 minutes.
Stir in the liver spread until it completely dissolves into the sauce. Add back the fried potatoes and the green peas. Let everything simmer until the potatoes are heated through.
Add the grated cheese and stir until it melts completely into the sauce. Taste and adjust the seasoning with salt and hot chili sauce if you want it spicier.
Serve hot with freshly cooked rice. The entire cooking process should take about 45 minutes, and this recipe serves 4-6 people.