Crumpets with jam are a supper staple in our household. Here are a few ideas to make them a little more healthy. In terms of the butter/margarine debate: there's lots of new evidence that suggests that, in moderation, butter is not as bad for you as once thought. However, if you do want to steer clear of butter, then do make sure you pick a margarine that doesn't have any transfats (avoid anything "hydrogenated"), which are even worse than saturated fats.
Put the blueberries, water, and sugar substitute in saucepan over a medium heat. Cook for 15 minutes until glossy and thick. This is a quick cheat for jam, easy to make, and without the high sugar content of a traditional jam.
Meanwhile, wash the strawberries and raspberries, and the slice the strawberries thinly.
Sterilise a small jam pot (although there probably won't be any left!) by washing it and then (while still wet) popping it in the microwave for 30 seconds.
Toast the crumpets, and butter them generously.
Arrange the strawberry slices and raspberries on the crumpets.
On another crumpet, spoon over a generous helping of blueberry jam.