Caramelized Onion and Tomato Galettes

June 23, 2022marissamakes
Caramelized onion and tomato galettes, styled on a baking tray and surrounded by colorful tomatoes and green herbs.

Prep time: 2 hours

Cook time: 1 hour 15 minutes

Serves: 6 mini galettes

I’ll admit I am a late-stage tomato convert. Growing up, I was never a fan of tomatoes, particularly raw ones. As I’ve gotten older, I’ve come to appreciate these magnificent gems, and all of their uses in the kitchen. One of my favorite ways to celebrate the arrival of summer is with this caramelized onion and tomato galette. It’s very easy to make. But between the caramelized onions, roasted tomatoes, and a pastry loaded with black pepper and herbs, it’s packed with flavor. This recipe makes six mini galettes. It’s perfect for your next dinner party al fresco, or summer picnic!

THIS POST MAY CONTAIN AFFILIATE SALES LINKS. 

What is a galette?

A question I often ask from my non-baker friends is “what the heck is a galette?”. It sounds extremely fancy, but is actually quite the opposite. Simply put, a galette is a freeform tart, meaning it does not use a tin or dish to create the shape. It’s a rustic sort of pastry, but its simplicity makes it a favorite of mine for using up anything that’s been lurking in my kitchen a little bit too long. You can make sweet galettes, or savory ones, like in this recipe. There’s no special equipment required, and in my opinion, the more imperfect it looks, the better.

How to caramelize onions

Oh, the humble caramelized onion. So simple, yet so complex and saturated with sweet and savory flavor. The word “caramelize” might sound intimidating, but it’s actually one of the simplest methods of getting flavor into your food. As food heats up on the stove or in the oven, the natural sugars begin to brown. This results in a deliciously nutty flavor, that’s sweet, but in a very grown up way so to speak. And it’s a great way to fancify onions in a pinch.

I recommend using a heavy bottomed pot, such as a dutch oven, as this helps get the proper heat retention you need for good caramelization. It’s going to seem like you have way too much onion in this recipe, but trust me, you do not! Your full-to-the-brim pot of onions will reduce down to a bit more than a cup. The trick to proper caramelization is patience: you need to tend to the onions so they brown, but don’t burn. It takes a while for them to start taking on color, but once they do, you need to keep a watchful eye and stir so that all your hard work doesn’t go up in smoke. It takes about 40-50 minutes to get a really lovely deep color on your onions: I promise that it’s worth it!

Once your onions have cooked down, are beautifully brown and almost creamy in texture, you’re done! Give them a taste before you use them for the galettes: I definitely won’t judge if you sneak a couple spoonfuls of plain caramelized onion 😉

How to make the perfectly imperfect galette

This recipe, like the majority of my pie and tart recipes, calls for a batch of my favorite pie dough, with a few alterations to the recipe. I love to add flavors to my doughs, as I find it’s an easy way to make recipes just a little bit more delicious and special. To the base recipe, you will add 1.5 tablespoons of ground black pepper, 1.5 tablespoons of chopped fresh oregano, and 1.5 tablespoons of summer savory. If you can’t find summer savory, you can replace with a blend of fresh thyme and rosemary.

Galettes are much simpler than tarts and pies to make, but you still need to bear some cardinal rules in mind. Keep the dough cold, and handling to a minimum so that the butter doesn’t leak out. When you roll out the dough, aim for some resemblance to a circle, but it does not need to be perfect. To assemble the galettes, place a few tablespoons of caramelized onion onto the dough circle, leaving about 1/2″-1″ of space around the edge. Layer a few slices of tomato on top, then fold over the edge of the dough and pleat to seal.

To serve, sprinkle the tarts with some flaky salt, fresh herbs, and a little bit of crumbled feta, if you like.

This recipe makes 6 mini galettes, but you can also make two large ones, if you prefer!

How to choose the right tomatoes for these galettes

It might sound silly to say there’s a right and a wrong type of tomato for this tart, and truthfully, you really can’t go wrong. However, I do suggest you pick tomatoes that are on the firmer side, because this will make it much easier for you to slice them. I love to use heirloom tomatoes. because their gorgeous colors and funky shapes make them perfect for simple decoration. You can also use cherry tomatoes, plum tomatoes, or a mix of whatever beauties you happen to find at your market.

What tools do I need?

The beauty of galettes is that they don’t require any special tools. That said, I do recommend using a heavy bottomed pot, such as a Dutch Oven for caramelizing the onions, and a Mandoline slicer for cutting the tomatoes. My favorite one is from DeBuyer! I use the La Mandoline Kobra, but they have a few different ones that are fantastic.

How to serve and store these galettes

Allow the caramelized onion and tomato galettes to cool before storing. They keep best in the fridge, wrapped well in foil, for up to 5 days. You can enjoy them cold, or bring them to room temperature before eating. They are sturdy little tarts, and pack well for lunch, or for a picnic.

I hope you enjoy this caramelized onion and tomato galettes recipe! Be sure to tag me on instagram so I can see your bakes, and leave me a comment below! Your feedback helps other bakers who are giving this recipe a try, and I love hearing about your bakes!

View Print Layout
Print Recipe
Close Print
  • Prep time: 2 hours
  • Cook time: 1 hour 15 minutes
  • Total time: 3 hours 15 minutes
  • Serves: 6 mini galettes

One of my favorite ways to celebrate the arrival of summer is with these caramelized onion and tomato galettes. They're very easy to make. But between the caramelized onions, roasted tomatoes, and a pastry loaded with black pepper and herbs, they're packed with flavor. This recipe makes six mini galettes. It's perfect for your next dinner party al fresco, or summer picnic!

Ingredients

For the galette dough

  • 1 recipe my favorite pie dough , see notes, with sugar omitted and the below herbs added:
  • 1.5 tbsp ground black pepper
  • 1.5 tbsp chopped fresh oregano
  • 1.5 tbsp chopped fresh summer savory, (sub with fresh thyme and rosemary)
  • 1 egg, lightly beaten with water, for egg wash

For the galette filling

  • 3 large yellow onions, (about 8 cups) sliced
  • 2 tbsp avocado oil or butter
  • pinch kosher salt
  • 3-5 heirloom tomatoes, sliced thinly
  • flaky salt, for finishing
  • fresh herbs, for finishing
  • crumbled feta, optional, for finishing

Method

Make the dough

  • 1)

    Make the dough according to the instructions here, omitting the sugar, and with the addition of the black pepper, and fresh herbs to the mix of flour, butter and salt.

  • 2)

    Divide the dough into two flattened disks, and wrap with saran wrap. Chill for at least 2 hours, or overnight,

  • 3)

    When ready to bake, remove the dough from the fridge and allow it to sit at room temperature for about 5 minutes before rolling.

  • 4)

    Using a sharp knife or bench scraper, divide the dough into 6 equal pieces, and gently press each piece back into a semi-round shape, taking care not to handle them too much.

Make the caramelized onions

  • 1)

    Cut your onions in half, so that each half has part of the root ball on the end. This will help your onion stay together as you cut. Slice your onions crosswise, in roughly 1/2″ slices.

  • 2)

    In a heavy bottomed pot or Dutch Oven, heat the avocado oil or butter over medium high heat. Add the onions, stirring to coat them in the oil. Cook the onions until they begin to soften and turn translucent, about 10 minutes.

  • 3)

    Sprinkle the onions with a pinch or two of kosher salt, and reduce the heat to medium low. Continue to stir every few minutes, and cook the onions for about 30-40 minutes more, or until they are deeply brown, jammy, and fragrant. Be sure to stir so that they do not burn and stick to the pot.

  • 4)

    When your onions are done, taste for salt and add more if desired. Allow to cool to room temperature before proceeding with assembly.

  • 5)

    While the onions are cooling, preheat the oven to 425 degrees F.

Prepare the tomatoes and assemble

  • 1)

    Thinly slice your tomatoes into disks using a sharp knife or mandoline slicer.

  • 2)

    When the caramelized onions are cool, begin to roll out your dough portions into circles roughly 1/4″ thick.

  • 3)

    On a parchment lined baking sheet, fill each dough circle with a few tablespoons of onion filling, leaving about a 1/2″-1″ border around the edge. Top with a few layered slices of tomato. It is easier to assemble the tarts on the baking sheet, rather than moving them after assembling.

  • 4)

    Fold over the uncovered edge of dough and pleat to create a circle. Repeat with the remaining galettes.

  • 5)

    Egg wash each galette with a pastry brush.

  • 6)

    Bake for 15 minutes at 425 degrees F, and then reduce the temperature to 375 degrees F. Continue baking for another 20 minutes, or until the pastry is golden brown and baked.

  • 7)

    Sprinkle the baked galettes with flaky finishing salt, some fresh herbs, and feta crumbles, if desired. Enjoy!

Notes

The recipe for my favorite pie dough can be found here.

Leave a Reply

Previous Recipe