Cut the sugar snaps in half lengthways to reveal their tiny peas. Peel and thinly slice the garlic. Warm the olive oil over a medium heat in a heavy based, shallow-sided pan, then add the garlic, letting it fry for a minute or two till fragrant.
Remove the garlic, it has done its work (you can put it in the salad later if you wish).
Add the sugar snaps, turning them every few minutes, until they darken a little, then add the hot water, the two slices of lemon and a little salt, partially cover with a lid, then leave to cook until the water has almost disappeared.
Trim the samphire and add to the pan, then immediately cover and remove from the heat. Melt the butter in a frying pan, then add the breadcrumbs, turning them over in the butter till lightly crisp and golden.
Chop the brown shrimps, then fold them into the crumbs, together with the parsley and a little rather coarsely ground black pepper.
Spoon the sugar snaps, samphire and any cooking liquor left in the pan onto a serving dish, then scatter the shrimp and crumbs over them. If you wish, add the reserved fried garlic.