- 1 1/2 tablespoon olive oil, divided
- 3 medium leeks, white and light green parts chopped (approx. 6 cups)
- 3 cloves garlic, minced
- 4 tablespoons chopped fresh rosemary, divided
- 2 medium sweet potatoes, peeled and thinly sliced
- 1/3 cup vegetable broth
- 3 tablespoons breadcrumbs
Preheat oven to 450F.
Heat 1 tablespoon oil in skillet over medium-high heat. Add leeks, garlic, and 2 tablespoons of the rosemary; saute 8 minutes or until leeks are softened. Season with salt and pepper if desired.
Arrange 1/3 of the sweet potato slices over the bottom of a 10-inch round casserole dish, overlapping slightly. Spread half of leek mixture on top. Arrange another 1/3 of sweet potatoes over leeks; top with remaining leeks followed by remaining sweet potatoes. Drizzle broth over top, cover with foil, and bake 35 minutes.
Stir together bread crumbs, remaining 1 1/2 tablespoon oil and remaining rosemary in a small bowl. Remove foil from gratin, and sprinkle with bread crumb mixture. Bake, uncovered, 15 minutes or until breadcrumbs are browned and crisp.