yes you can - I make mine using the hartleys powder sachets (which apparently equates to 4 portions.. I read somewhere that it's limited to 3 portions a day but I could easily eat a whole pint in one sitting! :-/) it's been a lifesaver for me... the ready made pots have more carbs in them though I believe..
You can also use the sugar-free jelly crystals to flavour fat-free natural yogurt. You don't need much - just a sprinkle. I do that if I want a 'pudding'.
Hi I too have found the Hartley jelly to be great for a "sweet" fix. Tonight i had a blackcurrant one with fromage fraise mixed with a little sweetner and a drop of vanilla essence, Now referred to as Vanilla cream..mind over matter!