Cooking and/or steam generating apparatus for the treatment and preparation of food in commercial kitchens; electric (high performance) deep fryers, gas (high performance) deep fryers, electric (high performance) frying pans, gas (high performance) frying pans, electric (high performance) pans, gas (high performance) pans as well as cookers, each for commercial kitchens; parts and accessories for the aforementioned goods as far as included in this class