potato, red onion + blue cheese tart

Gosh, I seem to have been in some kind of post-Thanksgiving funk these past 2 weeks! There was that big push to get recipes out to you before the holiday, and then I stopped cooking. Seriously, I was proud on nights that I picked up prepared sauce and fresh fettucini from the local pasta shop and managed to throw together a salad for the side. It has been a busy couple of weeks for our household, with me finishing up a bunch of photography projects and Brian wrapping up his most complicated website build yet. Hopefully life will return to a regular schedule these last weeks of 2011 (ha! when are the weeks before and after Christmas ever regular!) and I'll manage to get some holiday baking slipped onto my schedule!

This tart recipe has been on my list for, oh, about 3 months now. I'm not really sure why it popped into my head, but one day the idea of a potato tart with caramelized red onions and stinky blue cheese landed and stuck. Last Friday I finally got around to experimenting, first doing a little research to see how others had tackled similar recipes. I wasn't sure whether the potatoes should be cooked first etc., and luckily found a similar dish to launch mine from over at Smitten Kitchen. I can't even tell you how amazing this tart smelled as it was finishing its time in the oven. If only there were some way to bottle scent and upload it here on my Charlottesville computer, to be distributed to you all through your own computer speakers. Come on Apple, why haven't you figured that one out yet?

I guess you'll just have to make it yourselves, and I'm thinking a holiday potluck could be the perfect excuse. You know you have a few of those on your calendar...

I am so glad that I found the foundation recipe on Smitten Kitchen because I was alerted to the fact that the filling for the tart doesn't set up as solidly as a quiche would.  Good to know, because this cook likes to make sure her eggs are good and done, and I definitely would have over-cooked the tart had I not been warned.

Potato, Red Onion + Blue Cheese Tart

inspired by this recipe at Smitten Kitchen

serves 4 with a salad

Crust Ingredients (this is my favorite, all-purpose savory tart crust)

• 1-1/4 cups all-purpose flour
• 1/2 tsp salt
• 1/2 tsp chopped rosemary
• 8 tbsp unsalted butter, cut into 8 pieces
• 4-5 tbsp cold water

Filling Ingredients

• about 1 pound of potatoes (I used russet, but red potatoes would be fantastic too)
• 1 large red onion, sliced to 1/4-inch rings
• 1 tbsp olive oil
• 1 cup milk (I used 1%)
• 2 egg yolks
• 1/4 cup crumbled blue cheese (I used Ile de France Roquefort, which was sent to me as a sample to try)
• salt + pepper

Method

1. First, make the crust dough (about 1 hour before you're ready to assemble the tart). Place the flour, salt, and rosemary in a food processor and pulse several times to combine. Add the butter and pulse until the mixture resembles pea-sized crumbs, about ten 1-second pulses. Add the water, 1 tbsp at a time, and pulse briefly after each addition. After 4 tbsp of water have been added, process the dough for several seconds to see if it will come together. If not, add the remaining 1 tbsp water. Process just until the dough comes together in a rough ball. Do not overprocess or the dough will not be flakey. Transfer the dough to a lightly-floured work surface and knead briefly to for a smooth ball. Flatten the dough into a 5-inch disk and wrap it in plastic wrap. Refrigerate the dough for at least 1 hour and up to 2 days.  Note: My dough was very sticky with just 4 tbsp of water, so I wound up adding some flour to help it to come together. The final dough should be smooth and supple before refrigerating. Also, if you don't have a food processor, you can still make the dough by using forks or a pastry blender to cut the butter into the flour mixture, then add your water.
2. While the dough is chilling, prepare the filling ingredients.  Scrub the potatoes and remove any eyes or rough patches, leaving most of the skin in place.  Slice potatoe into 1/4-inch thick rounds. Place in a large pan and cover with water. Bring to a boil, and simmer for about 10 minutes until the potatoes are just tender. Drain and set aside.
3. Meanwhile, heat the olive oil over medium-high heat in a large skillet.  Add the onion rings and stir to coat with oil.  Drop heat to medium-low and allow unions to caramelize, stirring occasionally, for 20-30 minutes.  Remove from heat and set aside.
4. Whisk together the milk and egg yolks, set aside.
5. Preheat oven to 350℉.
6. After an hour, remove the dough from the refrigerator.  Roll to a round about 12 inches in diameter. Place the dough in a 9-inch tart pan with removable bottom.  Press the dough to the bottom and sides of the pan, and remove excess dough from around edge of pan.
7. Place cooked potatoes in concentric rings along the bottom of the pan, overlapping and adding layers until pan is full. Distribute the caramelized onions across the tops of the potatoes. Pour the milk/egg mixture over the potatoes and onions. Drop bits of blue cheese evenly across the surface of the tart.  Sprinkle with sea salt and freshly ground pepper.
8. Bake the tart for 45-55 minutes, until browning at edges.  Filling will still be slightly jiggly, as the milk to egg ratio doesn't allow for it to set as a quiche would.  The final consistancy should be creamy.