Rinse the squids whole, separating the bodies from its tentacles. Keep the fins and tentacles to use later for the filling. Trim the bottom of the squid body as shown in the video and make two parallel cuts at the end of the squid.
Cut the onion in brunoise and cook until browned in a Mibrasa casserole dish with olive oil. Add chopped mushrooms together with the squid fins and tentacles, sauté, and then add 2 tbs of tomato paste. Continue frying until the tomato has cooked through and then add the cooked bulgur wheat to the mixture and stir well.
In a preheated Mibrasa casserole dish, add a drizzle of olive oil with the squid and cook in the oven for 1 minute.
Fill the squid with the bulgur wheat and serve 3 to a dish. Garnish with sherry reduction and chopped chives or parsley.