Zucchini and Caramelized Onion Galette with Gruyere. Pure comfort food wrapped up in a buttery, flaky pastry. vegetarian
Zucchini is a transitional vegetable and one that I am up to my ears in, currently. Zucchini and caramelized onion galette with gruyere is definitely a comfort food and is a beautiful way to welcome the changing season. Hello Fall (almost)! Comfort food season is officially on as the long, leisurely days of summer start to wane.
I’m excited to share my go-to pastry dough recipe. I use it for galettes, pies, hand pies and quiches as well as pot pies and shepherd’s pie. It is over the top delicious and versatile. What makes it so delicious is the buttermilk (oh and lets not forget the butter) because it tenderizes the gluten strands in the flour and helps to relax the dough.
The most important part of making pastry is to handle the dough as little as possible and to keep. it. cold. If at anytime your pastry starts sticking to your work surface or fingers, its time to pop it back in the fridge for at least 10 minutes.
I prefer to make the pastry one day before I need it because the longer the pastry rests in the fridge, the easier it is to work with. If you’re comfortable working with pastry, then you can make the dough the day you plan to use it. Just make sure you let it rest in the fridge for a few hours.
Tools I use to make pastry dough include a maple rolling pin and a bench scraper. The bench scraper helps keep all the bits of butter and flour together and makes cleaning up my work space a snap. Also, a pastry cutter comes in handy when cutting the butter into the flour. It keeps the heat from your hands off the butter that you’re attempting to keep cold.
There are a few ways to prepare the shredded zucchini. I use a microplane grater to shred the zucchini, but a box grater will work too. After salting the shredded zucchini, I let it rest in a colander, then use a towel to squeeze out the liquids. An alternative method is to place the zucchini in cheese cloth over a bowl or large measuring cup. Then salt the zucchini, rest, and squeeze out the liquid through the cheese cloth.
Caramelizing the onions makes this recipe over the top delicious! The sweet, smoky, and creamy caramelized onions blend beautifully with the gruyere and spices and tie this galette together.
Remember, this is a rustic galette, so the uneven, craggy edges are ok! In fact, they are desired!
For a ‘covered’ dish, this zucchini and caramelized onion galette travels with ease. Wrap it in foil and place it on a large cutting board to carry it to your event. If needed, reheat it in an oven or mini oven at 350F right on the foil on a sheet pan, for about 15 minutes. Leftovers reheat easily too! Just never microwave any pastry, if you can help it.
Zucchini and Caramelized Onion Galette with Gruyere
Ingredients
For the Pastry:
- 1 1/4 C White Whole Wheat Flour *See Note, 6 3/4 oz
- 1 1/4 C All Purpose Flour, 6 1/4 oz
- 1/2 tsp Sea Salt
- 2, 8 oz Sticks of Butter, cold
- 1/2 C Milk
- 1 Tbs Apple Cider Vinegar
- 2 Tbs Water, ice cold
For the Galette Filling:
- 4 lbs Sweet Onions, (about 4 smallish )
- 3 lbs Zucchini, (about 6 small)
- 1 C Gruyere, grated (8 oz)
- 1 Tbs Olive Oil
- 1 Tbs Butter
- 2 tsp Sea Salt, divided
- 1 tsp Granulated Sugar
- 1/4 tsp Ground Pepper
- 1/8 tsp Red Pepper Flake, dried, optional
- 1/4 tsp Tarragon, dried
- 1/4 tsp Thyme, dried
- 3 Sprigs Thyme, fresh for garnish
- 1 Tbs Egg + 1 Water
Instructions
For the Pastry**:
- **Make one day ahead if time permits
- Cut the butter, into 1/4" slices using a knife, or a bench scraper. Pop the butter in the freezer for 5 minutes while you prep the rest of the ingredients.
- Measure out the milk and apple cider vinegar and mix together. Let set for 5 minutes to sour (this is your buttermilk).
- Mix the flour and salt together in a large bowl. Get the cold butter out of the freezer and drop it into the flour/salt mixture. Use a pastry cutter or a fork to cut the butter into the flour. Stop working the butter into the dough when the butter pieces are about the size of almonds, or slightly smaller.
- Make a well in the center of the bowl and add the milk mixture. Use your hands to mix the flour mixture with the milk mixture. Dump the mixture out on a floured surface when the mixture resembles a shaggy mass. Use a bench scraper to gather all the bits of flour together shaping it and pushing it together. Make a well in the center of the dough and add 2 Tbs of cold water. Use the bench scraper to start folding and pressing the dough over and on top of its self, working in the water. Work quickly so the dough stays cold. Fold it over on its self about 9-10 times shaping it into a circular mass as you go, using your hands as needed. Flatten it out using a rolling pin to about 1/2" making sure it is in a rounded shape. Wrap it securely in plastic wrap and refrigerate overnight or for at least two hours.
Zucchini Prep:
- Grate the zucchini using a microplaner or box grater, reserving 1/2 of one zucchini. Cut the reserved zucchini into 1/8" slices to be arranged on top of the galette before baking. Set aside. Place the shredded zucchini in a colander over the sink and add 1 tsp of salt. Mix well. Let sit for 25 minutes.
- Place zucchini, in 1 C batches, on a kitchen towel. Squeeze out the liquid and place the shredded zucchini in a large mixing bowl. Set aside.
For the Onions:
- While the zucchini is draining, cut the onions in half and slice length wise cutting in thin 1/2 moon shapes. Melt the olive oil and butter in a large non stick sauté pan over medium-low heat. Place the onions in the pan with 1 tsp salt, and sugar. These will take about 30 minutes to caramelize. Stir occasionally.
Roll out the Dough:
- Remove the pastry from the fridge. Have ready a sheet pan, plastic wrap, parchment paper, flour for dusting, a rolling pin and ruler.
- Dust the work surface with about 1 Tbs of flour. Place the pastry on the work surface. Use the rolling pin to 'condition' the pastry by beating it down by about 1/4". Turn the pastry as you work it.
- Flour the rolling pin and the top of the pastry to keep them from sticking to each other. Use the rolling pin to start rolling out the dough turning the dough 1/4 way around as you roll it out and the dough gets larger. Keep rolling, adding flour under and on top of the pastry as needed to keep the pastry from sticking. Work quickly, you want it to stay cold! If it's sticking too much, place the pastry on the parchment lined sheet pan and pop it in the fridge for 10 minutes. Roll the pastry out to 16" round. If there is a tear in the edge, tap your finger into a bit of water and seal up the tear.
- Place plastic wrap completely around the pastry (if it is not covered well, it will dry out in the fridge!) Place the dough in the fridge to rest for at least 20 minutes; 30 is better! Preheat the oven to 400F.
For Zucchini/Onion Mixture:
- In the large mixing bowl with the zucchini, add the caramelized onions, ground pepper, red pepper flakes, tarragon, dried thyme and gruyere. Mix well and taste for adjustment in seasoning. Adjust if needed.
To Assemble the Galette:
- Mix the egg and 1 Tbs of water well. Have a pastry brush ready.
- Assemble the galette on a parchment lined sheet pan. Spoon the zucchini mixture in the center of the pastry leaving at least 2" of crust on the edges. Begin folding the pastry inward, over the zucchini mixture. The pastry will overlap all the way around.
- Lay the 1/8" cut zucchini in a decorative overlapping circle on the open part of the galette.
- Brush the egg/water mixture over the pastry.
- Bake the galette for 45 minutes on the center rack, turning 1/2 way through the bake time.
- Let rest for 5 minutes, then cut using a pizza cutter.
- Garnish with fresh thyme leaves and flowers (if available).
Notes
**Making this pastry one day before you need it allows the dough to rest longer and yields a more pliable pastry to work with.
This galette serves 4-6 as a main or up to 16 as an appetizer.
The prep and cook time does not include the time it takes for the dough to rest. Recipe adapted from The Smitten Kitchen Cookbook.
Nutrition
Nutrition is provided as a courtesy and is an estimate. If this information is important to you, please have it verified independently.
Made it? Leave a comment below!
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I couldn’t trust any of the amounts, and luckily I made a practice before my dinner party.
The amount of butter is goofy. 2 sticks is 2 x 8 T, not 2 x 8 oz!
The amount of cheese is goofy. 4 oz grates up to be more than 2 c.
4 smallish onions is nowhere close to 4 lbs.
Instructions for whether you can assemble it all ahead and bake later would have been nice. I assembled it in the morning and it worked to bake that evening. I brought it out to room temp while I preheated the oven, and 45 minutes was still the right amount of time for baking.
I think if using sweet/Vidalia onions, you could use less sugar when caramelizing.
Hi Kathy! So glad the galette worked despite the goofy amounts of ingredients. How’d it taste?
It tasted great!