Sweet Potato Gratin

Slices Raw Sweet Potatoes A few bites into dinner, my husband stopped eating, inspecting his forkful of sweet potato gratin. “You’ve been experimenting again, haven’t you. We’d better write this one down…,” he said, with a smile.

Our 13-year-old leaped up, in search of paper and pencil, offering to serve as my secretary, before I “forgot” the recipe.

It isn’t necessarily that I forget to write down recipes as much as I resist it. Cooking has become a type of taste-science where I challenge myself to use on-hand ingredients in new and different ways. It can be something as simple as changing the type of cheese, for example, or using a different herb blend. Since becoming unfettered from recipes, my free-spirit, I’m afraid, has left my poor family wanting a little more consistency and same-old, same-old instead of a surprise party every night.

Gratin, by the way, is a French word which means something like, “baked layers of yummy vegetables, cheese and milk”. This sweet-potato gratin, was invented when I found myself red-potato-less, but having on-hand, a lovely three-pound bag of organic sweet potatoes. Pairing them with goat cheese, the resulting dish received a round of dinnertable-applause.

My poor family. Little did they know, their applause was not unlike clapping at the end of any great performance, never to be experienced quite the same way again. The mentioned they “always wanted their gratin made with sweet poatoes”. Fortunately, for me and my experimenting frenzy, didn’t say anything about all the other ingredients….

Since then, I’ve made the “same” recipe, in a dozen different versions and combinations. Leek replaces onions, raw garlic replaces freshly-made garlic paste; parsnips stand in for, or with, apples – depending on what I have on hand; and sometimes I use thyme, thyme with oregano, or only oregano, but always Greek, never Mexican.

Whether fresh cheese such as, goat, yogurt, ricotta or Quark, or smoky, salty, sharp or extra-sharp aged cheese, it is the cheese, much like the wine, that has the biggest flavor impact.

Last night’s entree were lamb shanks, braised low and ‘slow in a 225F oven – the best way to slowly render the fat, resulting in juicy, tender meat. The braising liquids began with an organic tomato sauce base to which I added organic molasses and apple cider vinegar, along with garlic cloves, sliced onions, a dash of sea salt and thyme. I selected an organic, aged sheep-cheese that had an incredibly rich and salty, nutty flavor – perfect for playing off the lamb’s light barbecue-sauce.

This is a very forgiving recipe – one that will allow you to experiment to your heart’s content, having fun with flavors.

Grain Lamb Leg Sweet Potato Gratin

Simmer gently for 10-minutes:

  • 2 cups milk
  • 1/2 tsp thyme
  • 6 peeled, whole garlic cloves
  • 2 bay leaves
  • 2 whole cloves

In meantime, using a mandolin with 1/8-inch thickness or a food processor 2mm slicing disc, slice:


  • 3 lbs peeled, raw, sweet potatoes
  • 2 medium onions
  • 2 medium apples (Pink Lady, Macoun, Cortland or Gala)


  • 2 cups parmesan or any other favorite hard, table-grating cheese
  • 2 cups Gruyere, Swiss, Manchego (use flavorful, aged cheese)


  1. 9×13 pan – Cut 1 clove garlic in half
  2. Rub bottom of pan with garlic halves, distributing garlic oil
  3. Rub 2 T butter on top of garlic oil
  4. Layer sweet potato slices in thin layer (about 1/4) of total sweet potatoes
  5. Layer onions (about 1/4)
  6. Layer apples (about 1/4)
  7. Sprinkle with salt, sprinkle with pepper
  8. Sprinkle 1/4 total cheese (mix parm and other hard cheese togethe for 4 cups total)
  10. Pour strained milk over layers (remove garlic cloves from milk and “tuck” into gratin)
  11. NOW layer cheese on top
  12. Cover with heavily buttered tin foil.
  13. Poke about a dozen 1-inch holes in toil cover with sharp knife (lets
    out excess moisture.
  14. Place 9×13 pan on larger cookie sheet (to catch drips if runs over)
  15. Bake at 350F for at least 1 hour. This can be baked with the lamb shanks or dishes in the oven at a 225F setting, but you’ll need at least 3 hours to bake the gratin. Plan accordingly.
  16. Test with knife to see if done.
  17. If watery (sometimes onions/apples/potatoes have more liquid than other times), remove the foil cover and allow to bake uncovered for the final 30-minutes, to evaporate some of the excess liquid.
  18. Allow to rest at room temperature, for at least 10-minutes before serving.