Potato and Sorrel Gratin

Preparation

1. Step 1

   Place potatoes in a wide saucepan and cover with water. Add salt to taste and bring water to a boil over medium-high heat. Reduce heat to medium, cover partially and gently boil potatoes for 20 minutes, or until tender all the way through but firm enough to slice. Drain, return the potatoes to the pan, cover and let sit for 15 minutes. Remove from the pot and using a towel to grip the potatoes if they are too hot to handle, slice about ½ inch thick, or if you prefer, cut in dice. Transfer to a large bowl.

2. Step 2

   Meanwhile stem and wash sorrel leaves. Heat a wide skillet over high heat and add the sorrel, in batches if necessary. Stir until sorrel has wilted in the liquid left on the leaves after washing. The color will go from bright green to drab olive and the sorrel will melt down to what looks like a purée. Don’t worry, it will be chopped and mixed with the other ingredients and you won’t mind the color. When all of the sorrel has wilted, remove from heat and transfer to a strainer or a colander. Rinse briefly with cold water, then press or squeeze out excess liquid. Chop medium-fine. Transfer to bowl with the potatoes, toss together and season with salt and pepper.

3. Step 3

   Preheat oven to 375 degrees. Rub sides and bottom of a 2- to 2½-quart baking dish or gratin with the cut side of the garlic clove. Oil dish with olive oil. Mince remaining garlic and add to potatoes and sorrel.

4. Step 4

   Beat eggs in a medium bowl. Add salt to taste (I use about ½ teaspoon). Whisk in milk. Add to potatoes and sorrel and stir well to distribute sorrel evenly throughout the mixture. Stir in cheeses and freshly ground pepper, and scrape into the baking dish.

5. Step 5

   Bake 45 minutes, or until set and the top and sides are nicely browned. Remove from the heat and allow to sit for 10 minutes or longer before serving.