Scalloped Fennel-Potatoes au Gratin

Scalloped Fennel Potatoes DoneCooking with a twist … that’s how a lot of my ideas form: take an idea, an ingredient, a ‘classic’ creation and then ask the question “What if …?”

As you’ve seen from my previous post, I had prime rib on the brain and one of the comfort foods I love to serve alongside this rare treat are scalloped potatoes (au gratin).

I have to say, the name of the dish is one that is confusing as it is storied. What does it mean to call something “scalloped”? Well, by some accounts, to scallop is to slice thin (as in: escalloped); others theorize it is on account of the creamy cooking process (and the crusty top) that was a technique borrowed from scallops (exemplified in Coquille Saint-Jacques). To keep the etymology even more ambiguous, the “gratin” refers to both the dish used to cook these creations and the technique of forming the “crust” on top, usually with some combination of bread crumbs and/or cheese. In the end, it really doesn’t matter which purist definition applies because most renditions are true to form and mine is no different: thinly sliced root vegetables, cooked in cream, and baked in a shallow dish until a thin crust forms on top.

So here’s the twist — how to give this side dish more nutritional value without giving up the decadence that made it a classic? I toyed with a number of different additions but in the end I settled on fennel in my head.

Fennel gets a really bad rap and I dare say many people don’t even give it a chance because they assume it is going to taste like the more ubiquitous product that we associate with anise: black liquorice. Yes, I love black liquorice, but that’s not the reason I love fennel which has subtle, slightly sweet, and very springlike quality to it and, when cooked, bears little to no resemblance to anything you’d associate with liquorice. Trust me — it’s delicious … and it served as a wonderful counterpoint in this dish with the Parmesan, cream, and the starchy potatoes. And, best of all, it brings in some nutrients into this otherwise decadent dish. The little bit of ground fennel within and the fennel tops on top pull the dish together and give it the full twist I wanted.

Cooking Tips: One word: mandoline. And no, I don’t mean bluegrass instrumentation playing in the background while you prepare the dish. I’m talking about the classic French kitchen tool which if the pre-revolutionary French monarchy had known about, well, they probably would have better exemplified Liberté, Égalité, Fraternité … and kept their heads. I say this having once lost a fingertip in my own carelessness and lack of appreciation for the sheer power and sharpness of this devastating and yet amazing slicer. Yes, you can do this with a food processor, but it won’t be as symmetrical and you’ll likely end up with ‘broken’ pieces all over the place. And, yes, you can also do this by hand with a sharp knife, but it will probably take you 3xtimes as long and you won’t have the perfect thinness you might otherwise seek.

Final Note: If, like me, you want to cook your potatoes alongside a prime rib or something else in the oven, you’re going to have a problem with the heat being too low on account of the roast needing to be at 325ºF. My solution is three fold: (1) start the scalloped potatoes covered in foil (2) when the roast has about an hour left to cook, place the covered potatoes in the oven and cook covered until cream comes to boil, 30-40 minutes, then uncover (3) when you remove the roast from oven, turn oven to 375ºF and continue cooking another 20-30 minutes and turn oven to broil just near the end to further crisp them up if they need more colour.

Prep time: 30 minutes
Cook time: 60-70 minutes
Total time: 90 minutes
Servings:   8-10

Scalloped Fennel-Potatoes au Gratin


  • Scalloped Fennel Potatoes Ingredients2 lbs (1kg) red potatoes, washed but not peeled
  • 1 large white onion (10 oz/300g)
  • 1 large fennel bulb (1 lb/450g)
    → reserve any green fronds
  • 1 tablespoon (15mL) butter
  • 1 cup finely grated parmigiano reggiano
  • 1 teaspoon (5mL) ground fennel seed
  • 1½ cups (375mL) heavy whipping cream
  • 1 cup (250mL) milk (2% or homogenized)
  • kosher salt
  • freshly ground black pepper


  1. Preheat oven to 350ºF (175ºC) … or follow cooking tip above (under “Final Note”) for alternate method. Use butter to grease a 3 quart/litre (13″x9″) shallow pan.
  2. Complete your prep. Wash the potatoes, but don’t peel. Remove the top/tail of onion and outer skin, but don’t slice skin. Cut away tops of fennel (but reserve the green fronds) and cut away the tough bottom core of the fennel. Grate your parmigiano reggiano. As well, unless you’re using pre-ground fennel powder, grind the fennel with a mortar and pestle and set aside. Remove the green fennel fronds from the stems and lightly chop.
    Grind Fennel Seed
  3. Set up your mandoline or food processor to slice about 1/4″ (1/2-cm) thick — or even a bit thinner — and using the guard, slice the potatoes and set aside.
    Slice scalloped potatoesRepeat and slice the onion …
    Slice scalloped onions… and finally, repeat with the fennel.
  4. Layer the au gratin now using the following layering instructions:
      1. Layer Potato
      2. Layer Onion
      3. Sprinkling of salt and Pepper
      4. Sprinkling of parmigiano reggiano
      5. Layer Potato
      6. Sprinkling of salt and Pepper
      7. Sprinkling of parmigiano reggiano
      8. Layer of fennel
      9. Sprinkling of fennel powder
      10. Layer Potato
      11. Layer Onion
      12. Sprinkling of salt and Pepper
      13. Sprinkling of parmigiano reggiano
      14. Layer of fennel
      15. Sprinkling of fennel powder
      16. Sprinkling of parmigiano reggiano
      17. Sprinkling of fennel greens

    Layer the Scalloped PotatoesSprinkle the Parmesan on PotatoesLayer the Scalloped FennelSprinkle the Fennel Greens on Potatoes

  5. Mix the cream and milk together and evenly pour it over the layered veggies.
    Pour the Cream Over Potatoes… and it should fill up about halfway up the sides of the baking dish.
    Pour the Cream Over Potatoes - Filled
  6. Cover dish with foil and bake, covered, at 350ºF (175ºC) for 30 minutes or until it reaches ‘boil.’ Remove foil and continue baking for another 30 minutes or until potatoes are fork tender (and easily break with fork). If top of dish hasn’t browned enough, put under broiler for a few minutes until desired crispiness is reached.
    Scalloped Fennel Potatoes ReadyRemove, let stand 15 minutes (allow cream to cool and thicken before serving), slice into squares, and serve alongside your favourite food … like Pesto Crusted Prime Rib.

Prime Rib Plated1


    • says

      Thank you Julie. Yes, I dare say fennel is more widely embraced in Europe than it is here in Canada. As for the mandoline, well, not the most portable thing when you’re travelling around the world. Go the route of the sharp good quality chef’s knife, pour yourself a nice glass of wine, and settle in for some careful slicing. I’m sure it will taste even better done by hand :)

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