Preheat the oven to 375° F. Use just enough oil to lightly grease the bottom of a 9-by-13-inch glass baking dish.
Peel the potatoes. Use a mandoline or food processor to slice them as thinly as possible (about 1/16 inch). As you work, transfer the sliced potatoes to a large mixing bowl to a large bowl. Add 3/4 cup of the heavy cream and toss to coat evenly.
Melt the butter in a large skillet over medium heat. Add the shallots and garlic; reduce the heat to low and cook for 3 to 4 minutes, stirring; do not let them brown.
Add the bay leaves, rosemary; pinch off pieces of the cream cheese to add it, along with the milk and the remaining 3/4 cup of cream. Whisk as you work to remove any lumps. Heat until the mixture is barely bubbling around the edges, then cook for 2 to 3 minutes, whisking constantly, until smooth. Add salt and pepper to taste; stir to mix well. Remove from the heat and discard the bay leaves. Pour the mixture over the potatoes in the bowl; toss gently to combine.
Transfer the potato mixture to the prepared baking dish. Sprinkle the potatoes evenly with the cheese and then with the bread crumbs. Bake for 60 to 75 minutes, until the potatoes are tender and the top is golden brown and bubbly.
Makes: 6