This is a lightened up Gratin which uses grated apple instead of the traditional cream to give the dish moisture so you can use less fat. I have to say that it's quite delicious and you don't miss the cream at all. It also uses equal parts sweet potatoes & Yukon Gold potatoes. Adding the sweet potatoes gives the dish great flavor and vibrant color but also adds beta carotene, fiber, iron, and calcium. Because we're using just a bit of cheese, choose one with full bodied flavor like Gruyere. I love Gruyere for its nuttiness yet saltiness and it melts wonderfully. A good fontina or even smoked Cheddar would be great here as well.
Make a big salad to serve alongside as it's an important light addition to the substantial gratin. This is truly a 'best of winter' salad featuring the beautiful fennel & green butter lettuce I'm seeing at the Market now and the Meyer lemons from my tree which are at their peak of ripeness.
Today is Sunday which for me also requires a pre-dinner wine and cheese hour. Tonight we're starting with Prosecco, Amaretto & Lime Cocktails (I'll share that recipe one day soon) and Cowgirl Creamery's newest cheese, Devil's Gulch with a crusty olive baguette. The cheese is a jersey cow's milk cheese with sweet and spicy red chile flakes. I hear it was all the rage at last week's SF Fancy Food Show. I'm a big fan of all their cheeses but this one is currently at the top of my list.
For the Gratin:
1# Yukon Gold potatoes, peeled and thinly sliced
1# Garnet sweet potatoes, peeled and thinly sliced
1 Granny Smith apple, cored, peeled, and grated
2 leeks, white & light green parts only, halved lengthwise and sliced into 1/4" half moons
4 oz Gruyere Cheese, grated
2 TB Pamesano Reggiano, grated
2 TB Olive Oil
2 tsp fresh thyme, chopped
1/2 tsp red chile flakes
coarse salt & freshly ground black pepper
1) Preheat the oven to 375 degrees. Toss together the potatoes, sweet potatoes, apple, leeks, olive oil, thyme, chile flakes, salt & pepper in a large bowl.
2) Transfer to a 9"x 13"x 2" baking dish, spread into a thin layer and cover with parchment lined foil. Bake for 15-20 minutes. Raise the oven temperature to 400 degrees. Remove the foil, top with Gruyere & Parmesan, and continue to bake uncovered until the potatoes are cooked through and the top is brown and melty and bubbly, about 30 minutes more.
For the Salad:
1 head Green Butter Lettuce, washed and leaves torn to bite-size pieces
1/2 fennel bulb
2 TB Italian parsley, coarsely chopped
2 oz Pecorino Romano, thinly shaved with a vegetable peeler
3 TB fresh Meyer Lemon Juice
zest of 1/2 Meyer Lemon
1 TB shallot, minced
1 TB Dijon Mustard
6 TB Extra Virgin Olive Oil
coarse sea salt & freshly ground black pepper
1) When the gratin is out of the oven and cooling, make the salad. In your serving bowl, zest the lemon, squeeze the juice, add the mustard, shallot, salt & pepper and whisk together. While whisking, add the oil in a steady stream to emulsify.
2) Add the sliced fennel to the bowl, right on top of the dressing. Place the lettuce & parsley on top of the fennel and set aside in the refrigerator until ready to serve. Right before serving, toss the salad and add the shaved Pecorino on top. Sprinkle the top with more finishing salt and a few turns of black pepper.