Having spent 30yrs as a female prison officer in male Prisons, it is likely sugar and boiling water was used.
Cutlery is plastic, but can be melted down by using a cigarette lighter, and melting the handle to a point.
Prisoners are allowed a razor blade, and the blade can also be melted into the handle of cutlery.
The kettle is an issue. In a similar setting tea in a big urn was accessible at certain times during the day, and prisoners would be allowed to get a cup of tea one at a time, supervised by 3 staff. That might sound old fashioned, but it saves staff being covered in boiling sugar and water.
Someone up thread mentioned that staff years ago were recruited from the military, who had life experience.. but now there is no common sense, no people skills, and an increasing number of female staff are becoming intimately involved with prisoners.
I enjoyed my job, and worked with some amazing staff, but I certainly wouldn't want to be doing that job today. Minimum staffing levels, a lack of common sense recruiting, and running a prison on a shoestring budget is just a recipe for disaster.