Place the potatoes in a pot of cold, salted water and bring to the boil. Simmer for 10-15 minutes until the potatoes are tender, then drain and set aside for at least half an hour to cool.
Fry the bacon in a non-stick pan until crispy. Set aside to drain on kitchen towel and slice into 1/4 inch strips when cool.
Place the asparagus tips in the frying pan with the bacon grease and sprinkle liberally with sea salt. Fry for a few minutes until they begin to soften but still retain their crunch. Set aside on kitchen towel to drain.
Halve the cooled potatoes lengthwise and place, cut side down, into the hot frying pan you've just cooked the bacon and asparagus in. Fry for a few moments just to brown the cut edge of the potato. Transfer to a plate.
To assemble the canapes squirt a little dollop of Heinz [Seriously] Good mayonnaise onto the browned cut edge of the potato. Top with two strips of bacon and one asparagus tip. Sprinkle with spring onions and serve.
You can serve these warm just after the potatoes have been fried, or cold.
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