Cooks across the Mediterranean appreciate fresh fennel for its celery-like crunch and faint aroma of anise. It’s often sliced thin and tossed raw into salads, finely chopped and stewed with beans, and roasted in wedges until darkened at the edges.

But we recently ran into trouble while trying to recreate another approach common to the region—a baked fennel gratin. Slicing the fennel thin, tossing it with olive oil, then baking it with a crispy Parmesan topping seemed straightforward enough. But each time, the fennel came out stringy and tough. More time in the oven didn’t quite do the trick, either.

It took American chef and cookbook author David Tanis to set us straight. In a recipe in his latest book, “David Tanis Market Cooking,” he blanches the fennel for about a minute before dunking it in an ice bath, a process that just barely tenderizes the fennel slices. The result, after baking, strikes the ideal balance between toothsome bite and jammy caramelized onion.

“If you tried to bake it raw, it wouldn’t have quite the same effect,” says Tanis, who spent three decades on and off at Alice Waters’ acclaimed Chez Panisse restaurant in Berkeley, California. “It would have to bake for too long.”

Armed with the right technique, we built upon his homey but sophisticated casserole, which incorporates fresh mozzarella, fennel seed, garlic, crushed red pepper and rosemary, plus a hearty glug of olive oil to help the flavors meld in the oven.

Since many supermarket mozzarellas lack the creaminess of harder-to-find fresh, we opted for a blend of shredded fontina and provolone. Mixing Parmesan into panko breadcrumbs created a solid crust that contrasted with the tender fennel beneath. And a sprinkle of fresh parsley added a pop of color and grassy notes to balance the cheese. The simple combination elevated the dish into something much more than the sum of its parts.

“This fennel al forno is just a further extension of a boiled veg with cheese and breadcrumbs,” says Tanis. “And what doesn’t taste good with cheese and breadcrumbs?”