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Caramelized Onion, Caper, and Mushroom Tart [Vegan]

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When it starts to get chilly out, there's nothing like a warm, bubbly tart to fill your belly. Having no crust, the creamy onion and mushroom filling in these tarts caramelizes beautifully in a hot oven. Add to that some fresh thyme and salty capers, and you've got yourself some very special tarts. Serve for dinner with a side of greens.

Caramelized Onion, Caper, and Mushroom Tart [Vegan]

This Recipe is :

Dairy Free Vegan


For the Pastry:

  • 1 1/3 cups flour (white or whole grain, whichever you prefer)
  • 1/3 cup vegan butter
  • A cup of ice cold water
  • A pinch of ground sea salt

For the Filling:

  • 3 tablespoons extra virgin olive oil
  • 5 garlic cloves, minced
  • 2 brown or white onions, finely sliced
  • 1 teaspoon sugar
  • 3 tablespoons capers (pickled and/or brined), roughly chopped
  • 10.5 ounces mushrooms, finely sliced
  • 3/4 cup, plus 2 tablespoons non-sweet vegan cream (such as cashew cream)
  • 1 tablespoon plain flour
  • 0.5 ounces fresh thyme leaves
  • Sea salt and black pepper, to taste


To Make the Pastry:

  1. This recipe makes two tarts.
  2. In a mixing bowl, combine the flour with a pinch of salt, then rub in the butter with your fingertips. You’ll get a mixture that looks like bread crumbs. To this, add some cold water, a tablespoon at a time, mixing and pressing the dough together with your hands as you do. You will not need all the water, just enough to form a smooth, pliable dough.
  3. Tip the pastry out onto a clean, floured surface and roll out with a rolling pin to a thin, even sheet. Press carefully into the tart dishes, trim, and refrigerate while you make the filling.

To Make the Filling:

  1. Preheat the oven to 435°F. Heat up the olive oil in a large frying pan. Over a medium-high heat fry the garlic and onion with the sugar until golden and caramelized, stirring frequently.
  2. Add the capers and mushrooms and continue frying. Once the mushrooms are fully cooked, add the cream and the thyme leaves (reserving a few to top the tarts), and cook for a further 5 minutes or so. Sprinkle in a tablespoon of flour and stir till thickened. Season to taste and stir again. Take off the heat and remove your pastry cases from the refrigerator.

To Make the Tarts:

  1. Spoon the hot mushroom filling into the tart cases. Bake for 10 minutes, then another 20 minutes or so at 390°F, or until the tarts are caramelized on top.
  2. Top the tarts with more thyme and serve hot or leave to cool and refrigerate.


Makes two tarts.





The best of hearty comfort foods made vegan. Vegan Lass (AKA Emily Wilkinson) is a Glasgow-based chef. Part-foodie, part-activist, she is known both for her hearty recipes and outspoken advocacy. Her work has been featured by numerous publications including The Scotsman, Vegan Life Magazine, Vegan Food and Living, T.O.F.U. Magazine, and Peaceful Dumpling. She also caters events and leads cooking classes. You can follow Vegan Lass on Facebook, Twitter, and Instagram, and check out her latest recipes over on www.veganlass.com. For all enquiries email [email protected]



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0 comments on “Caramelized Onion, Caper, and Mushroom Tart [Vegan]”

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andrea S
1 Years Ago

I made this tonight and it was very tasty. One thing though: half an ounce of fresh time is a LOT, and I didn\'t have that much so I used about 1 tablespoon of fresh and about a tsp of dried. I wonder if that was a typo? My tart had a very strong taste of thyme so I shouldn\'t want to use any more. Otherwise it was delicious!


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