Potato, Fennel and Leek Gratin—To Die For!

As promised when I posted our Easter Sunday braised lamb dinner, here’s the recipe for that luscious and so-decadent potato gratin side dish by Molly Stevens. The original recipe indicated it would serve 12, however with just the two of us (COVID-19 lockdown was still in effect), we halved the amount and still ended up with enough to feed eight.

Here’s where we went rogue. First of all, when we did the grocery shopping, there was no heavy cream to be had, so we bought light cream. You can create a substitute by adding butter, but with all of the cheese, I didn’t want to contribute even more calories and fat. In the end, the light cream worked out just fine since the starch from the potatoes naturally thickens it.

At the point where you are supposed to combine the potatoes and cream with the leek mixture, I opted to layer the ingredients instead. I was concerned that stirring everything together would break up the thin slices of potato and become a heaping mess as opposed to a more controlled layered dish.

The layers started with potatoes, followed by half of the leek mixture, then a layer of cheese. More potatoes on top of that cheese, the rest of the leek/fennel, the last layer of potatoes and finally all of the remaining cheese.

To Die For!

Potato, Fennel and Leek Gratin

  • Servings: 10-12
  • Difficulty: moderate
  • Print


  • 3 Tbs. unsalted butter, softened
  • 2-1/2 lb. Yukon Gold potatoes, peeled and sliced 1/8 inch thick (about 7 cups)
  • 2-1/2 cups heavy cream
  • 2 cloves garlic, finely chopped
  • Kosher salt and freshly ground black pepper
  • 1 tsp. fennel seeds, lightly crushed
  • 3 large leeks, white and pale-green parts only, trimmed, halved, and sliced crosswise 1/2 inch thick
  • 1-1/2 to 1-3/4 lb. fennel bulbs, trimmed, quartered, cored, and thinly sliced (about 5 cups)
  • 8 oz. Gruyère, grated (about 2 cups)


  1. Position a rack in the center of the oven and heat the oven to 400°F. Grease the bottom and sides of a 10×15-inch (4 quart) baking dish with 1 Tbs. of the butter.
  2. Put the potatoes, cream, garlic, 1-1/2 tsp. salt, and 1/2 tsp. pepper in an 8-quart pot. Bring to a simmer over medium heat and cook, stirring occasionally, until the potatoes are barely tender when pierced with a fork, about 8 minutes.
  3. Meanwhile, melt the remaining 2 Tbs. butter in a heavy-duty 12-inch skillet over medium heat. Add the fennel seeds and stir just until fragrant, about 30 seconds. Add the leeks and fennel, season lightly with salt and pepper, and cook, stirring occasionally, until just tender, 8 to 10 minutes.
  4. Gently mix the leeks and fennel with the potatoes. Transfer to the prepared baking dish, evening out the vegetables. Top with the cheese, and bake until the cheese is deep golden brown, the cream has thickened, and the potatoes are tender when pierced with a knife, 35 to 40 minutes. (If the top is becoming too brown before the vegetables are done, cover the gratin loosely with foil.) Let cool for 10 to 20 minutes before serving.
  5. If desired, sprinkle the finished gratin with fennel fronds for a pop of color.


Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s