Prepare the ingredients. Clean the fishes, and make sure that the innards have been removed. Follow the steps here, to know how to clean a fish. Score the fish for easier cooking. Prepare all the spices and vegetables. Season the fish with a generous amount of rock salt. Massage the salt into the fish and into the slits.
Cook the fish. Heat up a frying pan, and add half a cup of cooking oil. Let it heat up under medium low fire for a minute or two. Gently put the fish on the frying pan one by one. Do not overcrowd the pan, to ensure the heat is maintained to cook the fish properly. Cook each side of the fish for 3 to 5 minutes, depending on the size. Set aside all the cooked fish once done.
Cook the Escabeche sauce. Using the same pan and oil (as long as the oil still looks clear), sauté the minced garlic, onions, ginger, and bell pepper. Season with salt, Spanish paprika, and ground black pepper. Sauté and cook for 45 seconds. Add the carrots, and mix well for another minute. Add the vinegar, and let it simmer under low fire for 1 minute, or until the acidic smell evaporates. Add the soy sauce and brown sugar. Mix the brown sugar until it dissolves into the vinegar and soy sauce. Add the water, Knorr Liquid Seasoning, and banana ketchup. Let it simmer again for another minute or two, under low fire. Taste the sauce, and adjust according to your preferred acidity and sweetness. Add the sesame oil, and mix again.
Add the fried fish to the escabeche sauce. Once the escabeche sauce is ready, you can add the fish to the pan with sauce, and bathe the fish with the sauce, vegetables, and spices. Let it simmer for another minute.
Serve! Once done, arrange the fish on a serving plate, then pour the sauce over the fish. Garnish with green onions. Serve and enjoy while hot!