Cooking & Entertaining

Mostly Homemade Heirloom Tomato Tart

August 14, 2016

I have a ritual that I follow every Sunday evening starting in mid-July and continuing as long into the fall as I can: I walk down to the tiny store in my neighborhood and buy a mess of perfectly ripe home-grown tomatoes. Then, I’ll spend the week enjoying the deliciousness: alone with a little salt and pepper (so good!),  sliced and stirred into cottage cheese, or as part of a Caprese Salad. If I’m feeling extremely decadent, I’ll take  two slices of soft, white bread,  slather both slices with mayonnaise and make summer’s most delicious treat: the tomato sandwich. Ahhhh, so good!


But sometimes I want to do something a little more special for my summer dinners and for that, you can’t beat the Tomato Tart. It’s the perfect light and airy summertime dinner. It also combines my two favorite things to eat: perfectly ripe tomatoes and caramelized onions. Is there any word more beautiful than caramelized?

But caramelized onions take time and attention and who has the energy to add a homemade pie crust on top of that? The answer, of course, is lots of people, but I’m not one of them. I know my weaknesses and one of them is an inability to make a decent pie crust. 


Instead, I focus on what I can do and outsource the rest to the experts. In this case, that means using frozen puff pastry to create a light and fluffy crust for my tart. That makes it only mostly homemade, but also shaves a good hour of the preparation time. That means I eat my tart an hour earlier and so, I’m more than fine with the trade-off.


Ready to go into the oven. The tomatoes hide the layers of cheese and onion on the bottom.


Mostly Homemade Heirloom Tomato Tart

Prep Time: 30 minutes

Cook Time: 30 minutes

Total Time: 1 hour

Yield: 9 Large Slices

Serving Size: 1 Large Slice


  • 4 Tablespoons Butter
  • 2 Sweet Onions, Sliced Thin
  • Salt And Pepper, to taste
  • Frozen Puff Pastry
  • 1 cup Ricotta Cheese
  • 1/2 cup Grated Parmesan Cheese and an additional 1/4 cup Grated Parmesan Cheese for the topping
  • 1/4 cup Grated (or sliced thin) Mozzarella Cheese
  • 4 Medium Heirloom Tomatoes (I used a mix of red and yellow)
  • 1 whole Egg
  • 1/4 cup Milk
  • Basil Leaves


  1. Thaw the puff pastry as directed on the package.
  2. Preheat the oven to 425.
  3. Melt the butter in a large skillet over low heat and add the onions to the pan. Add salt and pepper (to taste) and sauté the onions for about 30 minutes or until a rich, deep golden brown, stirring occasionally.
  4. While the onions are cooking, thinly slice the tomatoes, add salt and pepper, and place the tomatoes between two paper towels to drain.
  5. Add the Ricotta, Parmesan and Mozzarella Cheeses to a bowl and mix together.
  6. Take both sheets of the thawed puff pastry and roll together until very thin. Drape the rolled out pastry over a baking pan and press into the pan, pressing the edges of the crust to the edges of the pan to make a crust. (Note: You can absolutely use two pie pans or even two real tart pans for this.)
  7. Layer the cheese evenly over the bottom of the puff pastry.
  8. When the onions are fully caramelized, even spread them over the cheese mixture.
  9. Layer the drained tomatoes over the top, overlapping the tomatoes to fully cover the pan.
  10. If you want extra cheesiness (and who does not?), sprinkle 1/4 cup grated Parmesan Cheese over the top.
  11. Combine the egg and milk to make a wash and brush on the exposed areas of crust.
  12. Bake for 30 minutes or until the crust is golden brown.
  13. The tomatoes will seem just a little too juicy when you remove it from the oven. That's ok. Add the basil to the top of the tart and then let it sit for 15 minutes. The tart will firm up and the basil will mix nicely with the other flavors during this resting period.
  14. Slice and eat!



  • Reply Gilly Maddison August 17, 2016 at 5:36 am

    Oh my goodness Katy – this sounds and looks delicious! I like the way you enjoy tomatoes from the simplest ways to the more sophisticated. I too used LOVE eating them the way you do with salt and pepper or in lovely fresh bread sandwiches with mayo. Sadly, I can’t eat raw tomatoes now – they sting my mouth and do all sorts of horrible things to me that they never did when I was younger – but I MISS them SO much! I can have them cooked so I will try this one day when I am feeling adventurous. (Or I may ask my husband to make it as he is the best cook out of the two of us 🙂 Thanks for the recipe! Will share on FB too.

    • Reply Katy August 17, 2016 at 12:11 pm

      Thanks for Sharing Gilly! Let me know what you think if you make the recipe

  • Reply Alexis November 27, 2016 at 5:33 pm

    This looks absolutely delicious!

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