Potato and Onion Tarts

Potato and Onion Tart 

My dear friend Jen, of Shortcake Biscuits with Warm Berries fame stayed at our house this weekend with her four kids and her husband. Thankfully, my friends are not dieting this year, so I was able to cook up some super decadent treats, including Nanaimo Bars (some of which got deep fried--yikes!), Toasty S'mores Rice Krispie Treats, Bisquick Velvet Crumb Coffee Cake, Dutch Letters, Waffle Sticks, and Pancake Sausage Dogs--just to name a few. I'd made fresh Dutch Letters and had some extra dough, which reminded me that I've been wanting to make these Potato and Onion Tarts for a while, ever since I purchased a copy of Martha Stewart's Baking Handbook. That Martha has a ton of incredibly delicious recipes in that book.
At any rate, these turned out even better than I'd anticipated. I wasn't so sure about the balsamic glaze, but it added the perfect finish to these deceptively hearty tarts. There's nothing I don't like about these. They've got the crisp, buttery puff pastry on the bottom, which adds a little chew and density; they yummy soft potato in the middle; the sweet, tender onions; and then the rich, buttery, savory balsamic glaze on top. To me, it's fancy comfort food. So satisfying.
If you don't want to bother making your own puff pastry, Pepperidge Farms makes a great frozen puff pastry dough. After you have the puff pastry settled, these are quick to make, and Martha says that you can prepare them a few hours ahead of time and refrigerate until ready to bake. Thanks again, Martha, for another fabulous recipe.

Potato and Onion Tarts (Potato and Onion Tartes Tatin)
--adapted from Martha Stewart's Baking Handbook

Ingredients:

• 4 tablespoons butter, cut into small pieces, plus more for pans 
• 1/4 recipe puff pastry dough (see recipe below) 
• 1 medium yellow onion 
• 4 smallish red or yellow skinned potatoes 
• Salt and pepper to taste 
• 1/4 cup balsamic vinegar 
• pinch of sugar 

Instructions:

• Preheat oven to 425 degrees Fahrenheit.
• Roll puff pastry dough out to about 1/4 inch thickness. Using the bottom of a mini pie pan or mini spring form pan as a guide, cut out four puff pastry circles. Prick each with a fork several times. Place on a plate or sheet pan and refrigerate until ready to use.
• Generously butter the bottom and sides of four mini pie pans or mini spring form pans. Set aside.
• Slice onion into 1/8-inch slices, making sure to keep circles together.
• Slice potatoes into 1/8-inch slices. 
• Place 2 or 3 onion slices on the bottom of each buttered pan so that it's somewhat evenly covered. 
• Place potato slices on top of the onions in an overlapping circle pattern. Place a single potato in the middle if it's not already covered by potato.
• Salt and pepper the potatoes.
• Bake at 425 degrees Fahrenheit for about 20-22 minutes, or until fragrant and the puff pastry is a deep golden brown.
• Carefully invert each pan onto a plate.
• Bring balsamic vinegar and sugar in a small saucepan over medium heat. Simmer for about 4 minutes, or until thickened and syrupy (you may want to reduce the heat once it comes to a simmer).
• Whisk in butter, one small chunk at a time into the balsamic syrup. 
• Drizzle a little balsamic butter syrup over each tart. Salt and pepper further, if desired.

Makes 4 individual tarts

Puff Pastry

Ingredients:

• 4 1/4 cups King Arthur Unbleached All Purpose Flour
• 1 teaspoon salt 
• 2 cups (1 pound) cold butter 
• 1 egg, beaten 
• 1 cup ice water

Instructions:

• In a large bowl, stir together the flour and the salt. Cut cold butter into half-inch slices and add to the flour mixture. Toss until butter pieces are coated with flour and separated from each other.
• Stir egg and ice water together and then pour all at once into the flour/butter mixture. Using a spoon quickly mix until you see no obvious wet spots. Butter will still be in large pieces and "dough" will be in shaggy bits and there will still be lots of flour that's not mixed in yet.
• Turn the dough out onto a large sheet of parchment paper (or a lightly floured pastry cloth if you have one). Knead the dough ten times or so by pressing and pushing dough together, using the parchment between your hands and the dough, to form a rough square shape. Using a little extra flour for the rolling pin, roll dough into a 15x10 inch rectangle. Fold 2 short sides to meet in the center. Bring the top edge down to meet the bottom edge to form 4 layers. You will now have a long rectangle about 7 1/2 by 5 inches.
• Repeat rolling and folding process once more. Wrap dough in the parchment paper you're using, and then wrap that in plastic wrap. Chill dough for 20-30 minutes. Repeat rolling and folding process two more times, and then chill the dough another 20 minutes before forming your pastries, whatever they may be.
• Once dough is chilled, preheat oven to 400 degrees Fahrenheit. Line a baking sheet with parchment paper.
• Cut dough into 4 equal pieces. 
• Use dough within 24 hours.

Maybe try making some Dutch Letters, Mini Apple Turnovers, Puff Pastry Pizza Pockets, or Two-Bite Chocolate Croissants with the remaining dough. Or you can just make more puff pastry pizza pockets and freeze them.