I got Jamie Oliver's "My Guide to Making you a Better Cook" as a present a year ago. There are certainly some nice ideas there and I have learned some things that I have not previously known. I was interested in the idea of getting fennel curly as a salad to go with a fish dish. Specifically he states

 Using a speed peeler, a mandolin slicer or pretty good knife skills, slice the fenner bulbs lengthways very, very finely and put in a bowl of iced water for 10 minutes or so until the slices go crispy and curly.

 Mrs O and I like fennel salad with smoked salmon or trout but I normally slice the fennel horizontally across the bulb (on my Siemens slicing machine) as 1 mm slices. I normally do a dressing with 2 parts vegetable oil to one of white wine vinegar or 3 parts walnut oil to 1 part of cider vineger.

I tried Jamie's idea a few times with water and a load of ice cubes and the fennel refused to curl. I ended up trying a bowl of water in the freezer with vertically sliced fennel. However it seemed to take a good 30 minutes to curl.

  crispy fennel

The result was more visually pleasing than normal, but seemed a real palava. Mrs O said it was a total waste of time and that the crisp chilled fennel had a much weaker taste than normal. However perhaps I made the mistake of using olive oil which tends to overpower more tastes than normal vegetable oil.