Remove the rind from the gammon steak, then cut it into strips approximately 5-7mm (¼") thick.
Bring a small pan of water to the boil, add the eggs and boil for 7 minutes, then refresh in cold water and peel them.
Cut the potatoes into a 5mm (just under ¼") dice.
Cut the red onion in half lengthways, then peel it and slice it into half-moon shapes as thinly as you can, and put them into a salad or mixing bowl.
Shred the salad leaves and add them to the bowl with the onions.
Place all of the ingredients for the dressing into a jar and give it a good shake.
Heat a 28cm or 11" non-stick frying pan over a high heat, and when it is hot, add the oil, then throw in the diced potatoes and the gammon and fry for 8-10 minutes. Then transfer to a plate lined with kitchen paper and drain.
Return the frying pan to the heat and when it is hot, sear the pineapple rings for 1 minute on each side, then remove and cut them into 4 segments.
Cut each egg into 4 wedges.
Dress the salad leaves and onion with all but a couple of tablespoons of the dressing and divide it between two bowls.
Top the lettuce leaves with the gammon, potatoes, pineapple and egg, then spoon over the remaining dressing and serve immediately.