Heat oven to 375° F. Peel the potatoes to within 1 inch of ends. Place a potato on the counter and put the handle of a wooden spoon along the far side of it. (The spoon handle will stop the knife from slicing all the way through the potato.) Cut the potato crosswise every 1/4 inch, leaving about a 1/2-inch uncut base. Repeat with the remaining potatoes.
Insert 4 bay leaves randomly between the cuts. Place the potatoes in a baking dish and drizzle with half the butter. Cover and bake about 45 minutes.
Uncover. Sprinkle with the bread crumbs and the remaining butter and bake, uncovered, 10 minutes more or until the crumbs are golden and the potatoes are tender.