I’m very excited to share this Caramelized Onion Mushroom Galette with you! Being from France, galettes are close to my heart, and this one has become a favorite in our home because it’s easy to make, packed with rich flavors, and totally satisfying. This galette features a rustic wholemeal spelt flour crust that’s topped with caramelized onions, mushrooms, fresh arugula, and a drizzle of balsamic glaze. The combination of savory mushrooms and sweet onions is divine, and the crispy, rustic crust ties it all together perfectly. The use of wholemeal spelt flour, makes it a nutrient-dense option, and of course it’s plant-based, and full of fiber, making it a nourishing meal that you can feel great about. I especially love to make this as an appetizer when hosting, but you could also enjoy it as a main (best paired with one of my protein-packed salads).
Whether you’re sharing it with friends or enjoying a cozy meal at home, this French-inspired dish will bring a little taste of France to your table!
Why I Love This Recipe
- Packed with flavor from the caramelized onions and fresh thyme, making it a truly satisfying dish.
- It’s fiber-rich with 5 g per slice, helping to support digestion and keep you feeling full longer.
- Wholemeal spelt flour provides a hearty, nutty flavor and adds extra nutrients like fiber and minerals to the crust.
- It’s versatile enough to serve as a main dish, appetizer, or a side, perfect for any meal of the day.
Ingredient Notes
- Yellow Onion: The star of the show, this onion caramelizes beautifully, adding a natural sweetness that pairs perfectly with the savory mushrooms. If you’re out of yellow onions, red onions can be used, though the flavor will slightly differ.
- Wholemeal Spelt Flour: This flour gives the galette a hearty texture and nutty flavor. If you can’t find spelt flour, you can substitute it with whole wheat flour or a mix of all-purpose and whole wheat flour. Spelt flour is high in fiber and adds a bit of protein to this recipe.
- Dairy-Free Yogurt: This adds moisture to the dough and helps bind it together. Choose a thick, unsweetened yogurt for the best results. I prefer soy for the added protein. Yogurt also adds a slight tanginess to the dough.
- Arugula (Rocket): Fresh arugula adds a peppery bite to the finished galette. It’s also rich in vitamin C and calcium.
How to make this recipe (summary)
Start by preheating your oven to 400°F (200°C) fan-forced for optimal baking results. Cook the onions and mushrooms on medium to low heat with a little olive oil, thyme, and seasoning until they’re perfectly caramelized and full of flavor. Prepare the dough by combining wholemeal spelt flour, dairy-free yogurt, olive oil, thyme, and a pinch of salt. Knead the dough until it forms a ball. Roll out the dough on a floured sheet of baking paper, then layer it with wholegrain mustard, caramelized onions, and mushrooms. Bake the galette in the oven for 30 minutes, rotating it halfway through for even baking. Finish by topping the slightly cooled galette with fresh arugula, a drizzle of balsamic glaze, and crumbled plant-based feta if desired. View recipe card below for detailed instructions.
Variations and Tips
- Substitute the mushrooms: This recipe is versatile. For a different texture and flavor, try with cremini, portobello, or your favorite mushrooms.
- Add a protein boost: serve on the side of your favorite protein or one of our protein-packed salads.
- Knead the dough just enough: Over-kneading can make the dough tough. Aim for just enough kneading to bring the dough together.
- Use fresh thyme: Fresh thyme gives the best flavor, but dried thyme can be used in a pinch. Just reduce the amount by half. Rosemary is a great alternative.
- Nutty twist: Add some toasted pine nuts or crushed walnuts for a nutty twist.
- Serve warm: This galette is best served warm, but leftovers can be reheated in the oven.
- If you like this recipe, you will love our Pesto Tomato Galette, or Olive Oil Shortcrust Pastry.
Why You’ll Love This Caramelized Onions Mushroom Galette TLDR
- Flavor-packed
- Hearty
- Nutritious
- Easy to make
- Versatile
Caramelized Onion Mushroom Galette
Equipment
- Rolling Pin
- Baking Paper
Ingredients
- 4 tsp (20 ml) olive oil - divided
- 1 large yellow onions - finely sliced
- 6 oz (170 g) mushrooms - sliced
- 3 tsp (4 g) fresh thyme - divided
- 2 pinches sea salt flakes - divided
- 1 pinch freshly cracked black pepper
- 1+1/4 cups (150 g) wholemeal spelt flour
- ½ cup (120 ml) dairy-free yogurt - I use soy
- 1 tbsp (15 g) whole-grain mustard
- 1 cup (20 g) arugula - rocket
- 1 tsp (5 ml) balsamic glaze
- 1 tbsp (17 g) plant-based feta - crumbled, optional
Instructions
- Preheat the oven to 400 °F (fan-forced).
- To a pan on medium to low heat, add 1 tsp of olive oil and the onions. Cook for 5 minutes, stirring regularly. Add the mushrooms, 1 tsp fresh thyme, pinch of salt and pepper, and cook for 15 minutes, covered, stirring regularly. Remove the lid, and cook for a further 5 minutes. Once cooked, set aside.
- In the meantime, prepare the dough: in a large mixing bowl combine the spelt flour, yogurt, 2 tsp fresh thyme, salt and 1 tbsp olive oil, using a spatula. You will get a crumbly result. Then using your hand knead the dough together for about a minute, until all the ingredients are incorporated, and formed into a ball. Use a little extra olive oil if necessary. The dough will be hard and compact and should not be sticky.
- Lightly flour a sheet of baking paper, and transfer the dough to the middle. Using a rolling pin, flatten the dough to your desired shape, to be approximately 2 to 3 mm (about 1/10 inch). If you want a perfectly shaped dough you can trim the edges with a knife, otherwise embrace the rustic look!
- Layer the wholegrain mustard on the dough, leaving about 1.5 cm (0.6 inch) of the outer layer bare for the crust. Top with the cooked onions and mushrooms.
- Bake in the preheated oven, on the middle to top rack for 30 minutes, rotating halfway.
- Allow to cool down slightly. Top with the arugula, a bit of crumbled plant-based feta if using, and a drizzle of balsamic glaze. Slice and enjoy!
Video
FAQ
Yes, you can substitute wholemeal spelt flour with whole wheat flour or a blend of all-purpose and whole wheat flour.
You can cook the onions and mushrooms in advance. Prepare the dough and assemble and bake the galette when you’re ready to serve.
Yes, this galette is completely plant-based and vegan-friendly.
If you’re not a fan of arugula, try using baby spinach or mixed greens for a milder flavor.
While it’s best enjoyed fresh, you can freeze the baked galette. Just reheat in the oven until warmed through.
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How can I make this gluten free?
I have not tested this recipe with gluten-free flour, I’m guessing something like Bob Red Mill GF flour could work 🙂 Let us know if you try 💚
Another delicious recipe! I added a whipped tofu base (tofu, garlic, nutritional yeast & apple cider vinegar), as well as sliced cooked beetroot.
Another delicious recipe! I added a whipped tofu base (tofu, garlic, nutritional yeast & apple cider vinegar), as well as sliced cooked beetroot.
That sounds delicious and a little fancy ✨ I think it would be beautiful for hosting, and I love how you’ve added protein to it!
Wonder if I could do
With buckwheat flour might give it a try ! What the worst that could happen
😂
I have not tried this exact one with buckwheat, but I tested something similar a while ago, and it sort of worked; it just was a little crumbly. Adding a bit more olive oil and a binder could help. Maybe a flaxseed egg?
Thank you x
I love the flavor and the combination overall! Also, loving the idea of using spelt flour and yogurt — much more nutritious. My galette did turn out a bit dense in its texture (less flaky). Any idea of the reason or any suggestions how I can adjust in the future? (Maybe I kneaded the dough a bit too much. I did add about one tablespoon of iced water and one more teaspoon of olive oil.) Thank you!
Can I use gluten free flour?
Thanks
I have not tried for this one, so I can’t give exact measurements but it should work, you will probably have to adjust the recipe a bit as all flour are a little different 🙂
You can, I’ve tried it works fine but I do add a little baking soda to the mix to give a bit of lightness. Delicious!
Thanks for your feedback. I will give a try!
You’re going to love this Caramelized Onion Mushroom Galette recipe! Make sure to rate it 5 stars and leave a comment if you enjoyed it!