Seriously Meatless: Caramelized Onion, Potato, and Blue Cheese Tart
Note: Please welcome Serious Eater Michael Natkin of the vegetarian blog Herbivoracious. He will be dropping by every Wednesday to share a delicious recipe to expand our vegetarian repertoire. This week, a savory tart. Take it away, Michael!

Most of my home-cooked meals tend to be both relatively easy and healthy--but this tart is definitely an exception. No getting around it, this is a bit of work and on the rich side. I think it's best served as a three-bite appetizer, where you can really enjoy the big flavors of the caramelized onions, smoked paprika, and blue cheese. I improvised it for an annual block party, and let's just say the entire sheet pan was gone in about 15 minutes.
I call for cabrales, a traditional Spanish cheese because it goes well with the smoked paprika, but you could just as easily use gorgonzola or another blue cheese of your choice.
The recipe will give you enough dough to fill a standard jelly roll pan, rolled out rather thin. You can also cut the recipe in half, roll it out thicker and bake in a 9-inch tart pan to serve in wedges. This sort of tart is best served warm or at room temperature after it sets up a little bit. You don't want to eat it piping hot from the oven.
Caramelized Onion, Potato, and Blue Cheese Tart
Ingredients
2 1/4 cups all-purpose flour (12 ounces)
8 ounces very cold unsalted butter (2 sticks), cut into 1/4" cubes
1/4 teaspoon salt
1/2 cup ice water
2.5 pounds onions, sliced (about 3 large or 5-6 medium)
1/4 cup extra virgin olive oil
1 heaping tablespoon smoked paprika (pimenton de la vera or pimenton dulce)
2 pounds Yukon gold potatoes, sliced 1/8" thick
1 cup heavy cream
1/2 pound cabrales, gorgonzola or other crumbly, meltable blue cheese
3/4 cup minced flat-leaf parsley for garnish
Procedure
1. In a large bowl, combine the flour, butter and 1/4 teaspoon of salt. Using a pastry blender or your hands, work the butter into the flour until it resembles coarse oatmeal. There can still be some larger bits of butter, that is fine. Don't work for more than 2 minutes at the most.
2. Add one half of the ice water and stir with a fork, trying to form a ragged ball of dough. As needed add more water a tablespoon at a time, but err on the side of using less. You want just enough to bring it together. Flatten into a rectangle, wrap in plastic, and refrigerate for at least one hour.
3. Saute the onions in olive oil in a large skillet over a medium-low flame until caramelized, about 30 minutes. Stir in the smoked paprika and season with salt to taste. They should be quite red in color. Reserve.
4. Combine the potatoes and cream with 1/2 teaspoon of salt in a microwave safe bowl and loosely cover. Microwave for five minutes, and then one more minute at a time until you can pierce with a fork but they are still holding their shape. The cream should have become quite thick at this point. You could also do this on the stovetop. Reserve.
5. Oil a standard half-size baking sheet (18" x 13", also known as a jelly roll pan). Preheat the oven to 400°F. Convection is fine if you have it.
6. Flour a board or your counter and roll out the dough until it about 2" larger than the sheet pan in both directions. Roll the dough onto your rolling pin, transfer to the pan and roll back out. Press into place, lining the entire bottom and sides. Prick in several places with a fork to prevent bubbling. Brush with a bit of olive oil to limit moisture entering from the vegetables.
7. Top the crust with a single layer of the potatoes. Distribute the onions evenly, then sprinkle on the gorgonzola.
8. Bake for 45 minutes to an hour, until the edges of the crust are golden brown. Peek underneath with a spatula and make sure it is well browned.
9. Remove from the oven and let rest for 5 minutes. Garnish with the parsley, cut into squares, and serve.
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16 Comments:
That looks delicious, I will try it this weekend. Thank you.
italiagirl84 at 2:29PM on 08/12/09
Wow, that sounds amazing!
KitchenMaus at 2:37PM on 08/12/09
This looks fantastic! Thanks for the recipe
MixedByHand at 3:15PM on 08/12/09
great.
have enjoyed reading the herbivoracious blog before,
look forward to your column here on SE
intheyearofthepig at 3:49PM on 08/12/09
Beautiful debut post, Michael! This looks delicious. Love me some blue cheese—and potatoes, and caramelized onion. Welcome!
Adam Kuban at 4:59PM on 08/12/09
Looks delicious! This is perfect for a party. Congratulations on the new gig!
lisal at 5:42PM on 08/12/09
Just needs a little chorizo!
DanielJ at 5:42PM on 08/12/09
I'd like to be at the next party this tart is at.
Tara Mataraza Desmond at 6:25PM on 08/12/09
Michael - I love your blog and am thrilled to see you have a column here on SE! Congratulations!
charm city cupcake at 7:29PM on 08/12/09
Thanks for all the support everybody! I'm excited to have a second home here on Serious Eats.
MichaelNatkin at 7:46PM on 08/12/09
This looks delicious! To make it a little simpler and quicker, could you use store-bought phyllo dough or puff pastry? I hate rolling out dough, I always fail. :-(
JGordon at 12:36PM on 08/13/09
@JGordon - I wouldn't do phyllo, but I think puff pastry would be good here. But you shouldn't be scared of dough! You are probably just having a basic technical problem - overworking it, too wet or dry, too warm or cold when rolling, that sort of thing. Once you get the knack you'll want to do it all the time. Pick up either The Art of Simple Food by Alice Waters or Ratio by Michael Ruhlman for straightforward but detailed instructions that will get you in the pastry dough comfort zone.
MichaelNatkin at 1:13PM on 08/13/09
Looks delish! Thanks for bringing more meat-free ideas to SE - looking forward to many more!
finewinendine at 5:17PM on 08/13/09
I don't like blue cheese - can I substitute, say, Gruyere or Gouda or something else? Thanks.
tomfodw at 11:16AM on 08/17/09
Well deserved recognition for Herbivoracious and Michael Natkin, nice work Serious Eats!
SavoryTv at 12:51AM on 08/18/09
I don't care for blue cheese either, but I've found that swiss makes for a delicious combination with onions, or gruyere as you suggested, if you strive to be oh so French. I actually this very humble onion tart that turned out delicious. It used low fat cottage cheese to create a creamy texture beyond what the swiss could provide. Not as beautiful as this version for sure, but oh so paupered and practical.
http://www.biggirlssmallkitchen.com/2009/01/potluck-parties-pack-pie-and-do-it.html
BigGirlPhoebz at 9:01PM on 08/19/09