Wash and trim the green beans and boil until just tender. Melt some butter in a pan, add the onion and the green beans and heat. Season to taste with salt and pepper if required.
Cut the potatoes into pieces and boil until just tender. Fry the potatoes in some butter until they are golden.
Slice some of the iceberg lettuce into thin strips.
Place the pancakes on the plates and arrange the roti, green beans, potatoes and finely sliced iceberg lettuce over the pancakes.