Theoretically this is a barakta question, while she's never broken a bone she's spent more time with her hands in plaster than most people have had hot dinners, and much of her day to day activities are one-handed or one-and-a-half-handed. On the other hand (or should that be the same hand?), many compensatory tactics involve skills that have taken a long time to develop and are bloody difficult when attempted by a normally able-handed person from scratch (eg. shoelaces).
Just don't try anything that requires draining or boiling water.
Slotted spoons work for the draining of coarser things (eg. pasta).
Too hard to co-ordinate and you can't steady a pan while stirring. Stick to fried stuff, risottos or simple stew type stuff. Or meals in microwave
Cooking is only half of the equation, unless you have a dishwasher
[1]. Pre-prepared and microwaveable food and learning to ignore/resent the middle-class snobbery is the winning tactic.
Chopping. Opening tins. All tricky one handed.
I got an electric tin opener and a mini food processor. I was also sent some of this which was useful to stop plates slipping away when you are trying to spread hummus/butter etc onto a toasted bagel
The cost:benefit balance for aids and adaptions may be very different for a one-off injury than for someone with a long-term disability. Of course some things are generally useful...
Beware of cooking gadgets that simplify eg. chopping but then leave you with additional, fiddly washing-up.
A surprising number of electric tin openers are unsuitable for one-handed operation. You may be able to get away with ring-pull tins and a lever. The stuff that needs an opener will keep, unless the cats develop opposable thumbs.
Get all the useful implements down from cupboards in advance - getting them down one handed from head height is harder than you might imagine.
Excellent point. Some re-organising of the kitchen might be prudent, if you can find someone to help.
On a related note, smaller bottles are much easier for one-handed operation. I'm thinking washing-up liquid, cooking oil, that sort of thing.
[1] Robot or human.