Dark Days Gratin: Root Vegetables and Leafy Greens

This versatile recipe comes in very handy during the “dark days” of winter when the local vegetable selection is limited. It’s flexible, it uses a lot of root and storage vegetables, and it makes a lot of food. It’s also delicious.

This time, we used sweet potatoes and an amazing braising mix that we bought from Keith’s Farm at the greenmarket. However, you can substitute any root vegetable and any leafy green. The last time we made it using parsnips, turnips, carrots, and swiss chard, and it was equally delicious.

If you’re in the deep of winter and you can’t get leafy greens you can always eliminate those layers (and the corresponding layers of herbs, cheese, and sauce) and make a more standard gratin. To keep it lively you can use a colorful mix of root vegetables. Eventually I’d like to try making it with white parsnips, orange carrots, pink turnips, and black radishes.

We found the inspiration and original version over at Smitten Kitchen, but we’ve made a number of substantial changes over time. Mostly we made it lighter, using less cream, butter, and cheese, and cut down a bit on the salt. It’s still every bit as tasty (OK, maybe not every bit), but now it’s a recipe that we can make all the time during the long winter without worrying about our waist bands.

The key with this dish is portion size. I could eat the whole thing in three sittings, no stretch of the imagination, but we try to resist seconds and huge portions. When we succeed it makes 7-8 servings.

Ingredients

Directions

This recipe is logically broken down into four separate preparations which are all combined in the end. That is how we have grouped the ingredients above (and why 1 tablespoon of butter appears in two places) and that is how we will present the directions.

Preparation 1: The sweet potatoes or other root vegetable(s)

1. Scrub and clean the root vegetables. For sweet potatoes there is no need to peel them, but if you substitute a different vegetable with a particularly tough skin you may want to consider it. Slice the root vegetables into thin rounds (1/8 inch). Although you can use a good knife to do this, it is much quicker work if you use a Mandoline Slicer.

   

2. Put the slices in a large bowl and set aside.

   

Preparation 2: The greens

1. If there are thick or tough stems on your greens, cut out the stems and chop them into small pieces (1/2 inch).
2. Dice the onion very finely. Melt 1 tablespoon of butter in a pot or sauté pan over medium-low heat. Add the onion (and the cut stems if you have them) and cook for about 5-8 minutes, until the onion softens and becomes slightly translucent. With the braising mix of greens that we used here, we had no need to remove stems.

   

3. Increase the heat to medium and pile the leafy greens on top of the onions. Add the pinch of nutmeg, a dash of salt, and a few grinds of pepper. If the greens don’t all fit at once you can add them in bunches about 30 seconds apart. They will shrink very quickly in the pan, providing additional room. Using a deeper pot such as a dutch oven would make this easier, but we are comfortable doing this in a shallow pan.
4. Using a pair of tongs, grab as much of the greens as you can and give it a 1/4 turn at regular intervals. This will place the fluffier uncooked greens on the bottom and give them a chance to cook down. It will also distribute the seasoning and onions. You don’t want to cook the greens down all the way because they will be cooked further in the oven. When you get to about the point pictured below, stop.

   

Preparation 3: The Béchamel sauce

1. Mince the 2-3 cloves of garlic. Place it in a microwavable dish or mixing cup and add the half-and-half. Microwave for about 1 minute on high. Alternately you could heat it by bringing it to a simmer in a separate sauce pan.

   

2. Melt 1 tablespoon of butter in a small sauce pan over medium heat. Stir in the flour, making a roux. Cook, while whisking, for about one minute. Slowly whisk in the warmed half-and-half (discard the garlic pieces) and bring to a boil while continuing to whisk. Season with a dash of salt and pepper.

   

Preparation 4: Miscellaneous

1. De-stem and chop the parsley and de-stem the thyme. Place together into a small bowl and set aside.
2. Grate the cheese into a bowl and set aside.

Final Construction

1. Heat the oven to 400 degrees.
2. Using butter, lightly grease the bottom and sides of a 9 x 13 baking dish, and place the various items that you have already prepared around it in an organized manner.

   

3. The final assembly consists of 8 layers (see below for the proper order and pictures):
   – 2 layers of sweet potato
   – 2 layers of greens
   – 2 layers of cheese and seasoning (herbs, salt, pepper), with sauce
   – 2 layers of cheese and seasoning (herbs, salt, pepper), without sauce.
   – It is finished with some extra cheese on top. I guess you could call that a 9th layer, but I prefer not to because I like symmetry.
4. Bake in oven (make sure the rack is in the middle) for 50 – 60 minutes. Let stand for at least 10 minutes before serving.
5. To avoid temptation, we like to portion it into 8 servings right away. For reheating, the oven is preferable to the microwave because it will retain the nice crispy/chewy texture that the top layer of greens will get. Heat the oven to 200 degrees and warm for 5-10 minutes.

   
   

Layers Illustrated

• Layer 1: 1/2 the sweet potatoes
• Layer 2: 1/4 quarter of the herbs, 1/5 of the cheese, salt and pepper

  

• Layer 3: 1/2 the greens
• Layer 4: 1/4 quarter of the herbs, 1/5 of the cheese, salt and pepper, 1/2 of the sauce

  

• Layer 5: 1/2 the sweet potatoes
• Layer 6: 1/4 quarter of the herbs, 1/5 of the cheese, salt and pepper

  

• Layer 7: 1/2 the greens
• Layer 8: 1/4 quarter of the herbs, 1/5 of the cheese, salt and pepper, 1/2 of the sauce; finish by sprinkling remaining cheese on top

  

With 8 servings, great leftover capabilities, and locally available winter ingredients, this is one of our favorites!