Sweet Potato Gratin With Maple Nut Crumble

Healthy, delicious and beautiful are all words that describe this sweet potato tian with maple nut crumble. Yams and sweet potatoes are thinly sliced and coated with olive oil and maple syrup, then stacked horizontally and roasted until perfectly soft and sweet. Maple sugar and chopped nuts are the perfect crunchy finish for a healthy Thanksgiving side dish your family won't forget.

For those who love to cook, Thanksgiving offers the opportunity to pull out our showstopping recipes and attempt to impress our families and friends. Depending on your family, this may or may not be successful, since sentiment and tradition tend to reign supreme at holiday meals. This sweet potato tian with maple nut crumble is a dish that aims to reach across the barrier; it's a Thanksgiving side dish that is unique, fun to make, and beautiful to look at, but still feels traditional.

Like many memorable Thanksgiving side dishes, this sweet potato tian is deceptively simple. It only requires seven ingredients and about 15 minutes to assemble. It does spend a good chunk of time in the oven, but it's a forgiving dish that can share the oven with your turkey. It can also be partially cooked and then finished off after your turkey is done.

Use maple sugar for a distinctive nut crumble

The maple nut crumble on top of this tian features maple sugar, which gives the nuts a nice coating of glaze, and just a bit of flour (optionally) to add some extra crunch. Maple sugar not only adds maple flavor to the nuts, it has a lower glycemic index than brown sugar. It also has antioxidant and nutritive properties that brown sugar and cane sugar do not, which is another reason I like to use it regularly. There's not enough in this recipe to make a huge difference nutritionally, but it's worth acquiring if you love the flavor of maple or are interested in sweeteners with a lower glycemic load.

You can find maple sugar at high end grocery stores, or on Amazon. It's also pretty easy to make your own maple sugar from pure maple syrup. It might take a time or two to get it right, however, so it's not something you want to be trying for the first time on Thanksgiving day. I recommend making your maple sugar the day before. You only need a tablespoon.

Ingredients and substitutions

Sweet potatoes or yams - You can use any type or combination of sweet potatoes and yams you want. White sweet potatoes are a little starchier, when I use them I prefer to mix them with yams. Buy more than you think you need, it takes a lot to fill up the pan. In any pan I've ever used, I've needed a minimum of 5 sweet potatoes.

Extra virgin olive oil - I recently switched to using Graza "Sizzle" Extra Virgin Olive Oil for roasting vegetables.

Pure maple syrup - Please, please, please no Log Cabin or any other maple-flavored syrup. Pure maple syrup. Grade A or B. 

Kosher salt - I test my recipes using Morton's kosher salt. 

Walnuts and/or Pecans - Pistachios and hazelnuts are also delicious.

Maple sugar - I use Coombs Family Farms Pure Maple Sugar, and I find it at my local grocery store or on Amazon. You can also make your own (see above).

Flour - All-purpose wheat flour, rice flour, or gluten free flour will work, although they all yield different textures of crumble. You can also leave it out altogether.

Tips for the perfect sweet potato tian

Generously oil your baking vessel. The maple syrup and maple sugar in this tian recipe make it prone to sticking to your pan, so it's important to be generous when brushing the pan with olive oil before you assemble it. You can also use a good cooking spray.

Slice your sweet potatoes thin. Tians generally consist of very thinly sliced vegetables, and you want them to almost melt together as they bake. The thickest they should be is about ⅛ inch. You can use a mandoline or a very sharp knife. 

Pack them in tight. The tian should almost roast as a tightly packed block. This doesn't mean you have to work hard at squeezing in one more slice, but definitely get them packed in there so they aren't leaning over. Use the end pieces to tuck into the corners if you are using a square or rectangular pan.