kale and potato gratin

Here is a simple, nourishing side-dish for fall: a light (no cream) gratin with shredded kale and potatoes. Our local farm has potatoes galore right now, and the kale is starting to be really delicious as the nights cool. This dish will take you into late fall/early winter and still be considered seasonal and local for those of us living in much of the northern hemisphere.
This recipe is unusual for having little to no dairy involved. Most potato gratins are loaded with milk or cream; this one lets the natural, sweet flavor of the potatoes come through. There is a little cheese for flavor, but this can be left out for a vegan adaptation. See the adaptation notes below.

1 1/2 pounds thin-skinned boiling potatoes such as red potatoes
1 bunch kale
1/4 cup olive oil
4 cloves garlic, minced
2 teaspoons coarse salt
1 teaspoon pepper
Between 1/3 and 2/3 cup bread crumbs
1/3 cup grated Parmesan cheese (optional) OR 3 tablespoons olive oil and 1 tablespoon minced fresh herbs, such as thyme or sage

Preheat oven to 350° F.
Get a pot of water boiling large enough to accommodate the potatoes. Also prepare an ice bath.
Meanwhile, slice the potatoes 1/4-inch-thick. Set aside. Remove and discard the spines from the kale then chop the remaining leaves in 1/2-inch-thick ribbons by stacking the leaves and slicing in the direction of the veins. This doesn't need to be exact, as long as you end up with a pile of roughly 1/2-inch-thick shreds of kale.
When the water is boiling, add a dash of salt and gently drop in the potatoes, cooking for about 2 to 3 minutes, until tender, but not cooked through. Drain and plunge into the ice bath. Drain again and dump onto a dish towel and blot.
In a large bowl, combine the olive oil, garlic, salt and pepper. Add the kale and rub the olive oil mixture aggressively into the leaves. Layer the kale and potatoes alternately with a sprinkling of bread crumbs and Parmesan in a 9"x12" rectangular casserole or glass or ceramic baking dish.
Vegan adaptation: If you want to leave out the Parmesan, double the bread crumbs to 2/3 cup. Rub the extra olive oil and the minced herbs into the breadcrumbs with your fingers until they are the texture of wet sand. Proceed as directed above, layering the bread crumbs between the potatoes and kale.
Cover with foil and bake for 30 minutes. Remove foil and bake another 15 minutes, until top is crispy.