Oh what a delightful subject. Aluminium cooking pots with folding handles, designed purposely to retain ingrained food in the corners. When used with a Gaz stove they're fine. When used with a Hexamine cooker they're an absolute cnut to clean and many a sprog will attest to the horror of removing the sticky black residue with nothing more than some wet grass and elbow grease - and still be expected to shave in the mirror-like polished surface within a five minute period.
Little changed since WW2, it's high time these horrors were consigned to the history bin, as far more suitable alternatives have been developed in the seventy-odd years since these things first saw the light of day. One of the many items every army surplus shop will always have in stock, claiming to be ex-issue, when they are the inferior aluminium versions.
Every Walt and cadet (of any disposition) normally has a set of two (one large, one small) in their possession, normally, the little delights 'in charge' of squadron/detachment/unit stores, has LOADS. They're welcome to them. Get yourself a decent metal '44 pattern mug. It's all you'll need.