Elegant (But Easy!) Caramelized Onion and Mushroom Tart

Tender pastry crust topped with caramelized onions and two kinds of mushrooms? That’s what I’m talkin’ about! This caramelized onion tart with mushrooms is going to knock your socks off.

silver pie scoop lifting up a piece of tart from a baking sheet

If you’ve made a batch of this addictive caramelized onion jam, it’s the shortcut to making this tart in a hurry. You can also use caramelized onions made just for this recipe. If you opt to do that, drizzle a few teaspoons of balsamic vinegar over the onions just as they’re finished for an extra pop of flavor.

Now let’s talk about the pie crust. You could use a store bought pie crust, but I need to take a moment to encourage you to try your hand at making pie crust at home. It’s such a vintage skill, and with my Grandma’s easy pie crust recipe, it’s hard to go wrong.

This tart uses a single pie crust. My Grandma’s recipe makes a double pie crust. This means you can use one now and pop the other half of the dough in the freeze for later.

Making this caramelized onion and mushroom tart

Instead of rolling the pie crust into a round as you would for a pie, roll it into a rectangle to fit a baking sheet. It should be about an eighth-inch thick. (Check out this technique for easy, non-stick rolling.) Pierce the crust with a fork eight to ten times; this allows air to escape, preventing a big bubble.

Once rolled out, gently spread the surface with softened cream cheese, then add the cooked onion mixture. Spread evenly, almost out the the edge of the crust. Bake until the crust is cooked through and lightly browned on the edges.

Cut into small squares, this mushroom and onion tart makes a great appetizer for dinner parties. Or serve it with a big green salad for dinner.

caramelized mushroom and onion tart from above

★ Did you make this onion tart recipe? Don’t forget to give it a star rating below! ★

mushrooms and onions spread on a flat pie crust

Caramelized Onion and Mushroom Tart

Yield: 6
Prep Time: 25 minutes
Cook Time: 25 minutes
Total Time: 50 minutes

The rich sweetness of caramelized onions pair with earthy mushrooms to make an easy, yet elegant tart.


  • 1 cup caramelized onion jam, or caramelized onions
  • 3 oz white mushrooms, sliced
  • 3 oz portobello mushrooms, sliced
  • 1-2 tablespoons water
  • 1 single pie crust
  • 4 oz cream cheese, softened
  • salt and pepper, to taste


  1. Preheat oven to 425 degrees Fahrenheit.
  2. Warm the caramelized onion jam over medium high heat in a large pan.
  3. Once the jam is heated through, stir in mushrooms and water. Allow mushrooms to wilt, about 3-4 minutes. mushrooms and onions on a wooden spoon
  4. Remove from heat and set aside.
  5. Line a baking sheet with a sheet of parchment paper.
  6. Roll pie crust into a rectangular shape about 1/8" thick; transfer to baking sheet. Use a fork to pierce holes in the crust. (8 to 10 times is sufficient.)
  7. Gently spread cream cheese over the pie crust, to within half and inch of the edges.
  8. Top with mushroom and onion mixture.
  9. Bake for 20-25 minutes, or until pie crust is cooked through and edges are golden brown.
  10. Allow to cool to room temperature before cutting and serving.
Nutrition Information:
Yield: 6 Serving Size: 1 grams
Amount Per Serving: Calories: 216Total Fat: 14gSaturated Fat: 6gUnsaturated Fat: 0gCholesterol: 21mgSodium: 180mgCarbohydrates: 19gFiber: 2gSugar: 3gProtein: 4g

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mushrooms and onions spread on a flat pie crust

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About the author: Claudie Evert is passionate about living lightly on the earth. She digs in the garden, cooks food from scratch, and will — someday — master the art of picking out a ripe watermelon.

3 comments… add one
  • Vivian Nov 16, 2020 @ 5:39

    I made this Keto with an almond crust. Really liked it!

  • Marie Aug 1, 2020 @ 10:49

    Just made your amazing tart, though I used my own carmalised onions as I did not have the jam. It came out so well that it didn’t last very long at all. Will certainly be making this again and again

    • Kris Bordessa Aug 6, 2020 @ 15:25


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