Heirloom Tomato Tart with Basil and Gruyere Cheese

Name: Heirloom Tomato Tart with Basil and Gruyere Cheese.
Prep time: 50 min
Cook time: 45 min
Total time: 95 min
Ingredients: 1 Unbaked single pie crust; 2 1/2 pounds assorted heirloom tomatoes; 2 teaspoon kosher salt; 1 cup chopped sweet onion; 1 3/4 cups grated Gruyere cheese; 1/2 cup grated Parmesan cheese; 3/4 cup mayonnaise; 1/3 cup basil chopped; 1 tablespoon chopped fresh thyme; 1/4 teaspoon pepper; 1 egg (lightly beaten)

Ever wandered around farmer’s markets on a sunny morning and been captivated by the vibrant colors and unique shapes of fresh heirloom tomatoes? Me too! Today, I’m sharing a dish that's the epitome of summer, the gorgeous Heirloom Tomato Tart with Basil and Gruyere Cheese. It's a marriage of flaky crust, sweet tomatoes, and aromatic herbs and a great way to make use of your bumper crop of summer tomatoes. So, grab your rolling pin and tart pan, and let’s dive in. The first time I made this I ate almost the whole thing the first day!

WHAT’S SO GOOD ABOUT THIS TART?

Beyond its sheer beauty, this tart is a canvas of textures and flavors. Imagine biting into a slice. The pie crust is a golden brown, tender yet sturdy enough to hold the juicy heirloom tomato slices. The basil's fragrance, paired with Gruyère and Parmesan cheese, takes me straight back to summer days when my garden was overflowing with fresh tomatoes and the aroma of fresh herbs. I can't find anything not to love about this tart of gorgeous summer tomatoes.

INGREDIENTS

For the full recipe with quantities, see the recipe card at the end of the post.

INGREDIENT NOTES

Heirloom Tomatoes: These aren’t your everyday tomatoes. Each one tells a story, and their unique flavors set this tart apart. My favorite is called Mr. Stripey.
Pie Crust: It’s the foundation of our tart shell. Go for a good quality one, ensuring the golden brown and flaky crust we adore. I use a refrigerated pie crust from the grocery store. I like the Pillsbury brand.
Gruyère and Parmesan Cheese: These cheeses are the soulmates of heirloom tomatoes. Their flavors meld beautifully, making every bite unforgettable.

SUBSTITUTIONS

Feeling adventurous? Try substituting the Gruyère with goat cheese or even a dash of ricotta cheese for a creamy twist.
Don't have heirloom tomatoes? You can use any tomato you like. This tart offers the best way to use an abundance of any tomato variety.
No fresh basil? Use fresh oregano instead!

VARIATIONS

While the original recipe is a classic, don't hesitate to add cherry tomatoes or even drizzle some homemade tomato sauce on top for extra zest.
Also, shredded mozzarella can be a wonderful addition to add a bit of gooey, melty texture.

Slice of tomato tart on a serving plate.

STEP-BY-STEP DIRECTIONS

Slice tomatoes into ¼-inch slices. Place the sliced tomatoes into a medium bowl and let sit for 30 minutes.

Place the crust in a 9-inch fluted tart pan. Press dough into the pan. Trim excess dough along the edges.

Lay slices on triple-thickness paper towels on a wire rack and sprinkle with one teaspoon of salt. Let sit 15 mins.

In a small bowl combine the Gruyere & Parmesan cheeses, mayo, basil, thyme, ½ teaspoon salt, pepper, and one egg.

Refrigerate the cheese/herb mixture covered with plastic wrap until ready to use.

Sliced tomatoes laid out on paper towels.

Pat tomato slices with a paper towel to remove excess moisture.

Add minced onion to the bottom of the pie crust.

Pie crust with a layer of cheese/herb mixture.

Top onion with ½ of the cheese mixture.

Tomatoes arranged on top of cheese mixture.

Layer ½ of the tomatoes over the cheese mixture.

Another layer of the cheese mixture over the tomatoes.

Top tomatoes with ½ of the cheese mixture.

Final layer of tomatoes placed on top of cheese mixture with shallot slices.

Repeat with another layer of tomatoes.

Fully baked Heirloom Tomato Tart with Basil and Gruyere Cheese.

Place pie on a baking sheet and place in oven. Bake for 40 to 45 minutes.

RECIPE FAQ's

Can I use store-bought puff pastry?

Absolutely. If you're short on time, a puff pastry can be a lifesaver. But remember, the texture will be different—lighter and more airy. Make sure you dock it (poking lots of holes in the bottom to keep the pastry from puffing up too much.

How do I ensure a perfectly baked crust?

Pie weights are great, but if you don’t have them, no worries. Lay down some parchment paper and use dried beans as a substitute. I keep a little jar of shiny copper pennies and I use them, on top of a piece of parchment paper to keep my bottom crust from puffing up and pulling the edge down. I rinse them off in a strainer after using them.

Storing the tart?

Always store it at room temperature covered with plastic wrap. Remember, fresh is best, so consume within a day or two!

PRO TIPS FOR SUCCESS

Dough: When rolling out your pie crust, a lightly floured surface and a rolling pin will be your best allies. Keep your pie crust chilled until ready to use for the best results.
Draining Tomatoes: Using a paper towel bundle to drain your tomato slices is crucial. We love their juiciness, but too much liquid could make the bottom of the crust soggy. Nobody likes that! If you take the time to draw the water out of the tomatoes your tart will be firm and easy to slice and the crust will stay flaky.