We aren’t going to try to stop you from serving tofu turkey if that is how you roll on Thanksgiving, but for a vegetarian main that can hold its own at the center of the table, this tart makes a very convincing argument.
Ingredients
6–8 servings
Crust
1
1
1
10
Filling and Assembly
4
4
3
2
4
½
1
1
1
2
2
Special Equipment
Preparation
Crust
Step 1
Whisk whole wheat flour, salt, and 1 cup all-purpose flour in a large bowl to combine. Add butter and work into dry ingredients with your fingers, smashing between your palms to flatten, until largest pieces are the size of a nickel. Drizzle in 6 Tbsp. ice water and rake in with your fingers. Gently squeeze handfuls of mixture together until a shaggy dough forms. Turn out onto a work surface and knead until only a few dry spots remain. Pat into a disk and wrap in plastic. Chill until very firm, at least 2 hours or up to 3 days.
Step 2
Roll out dough on a lightly floured surface to about ⅛" thick. Transfer to tart pan. Lift up edges and allow dough to slump down into pan. Gently press into corners and trim excess. (If using springform pan, trim dough to 1½" up sides of pan). Freeze until firm, 15–20 minutes, or cover and chill up to 12 hours.
Filling and Assembly
Step 3
Place a rack in lower third of oven; preheat to 350°. Swirl 2 Tbsp. oil in a large skillet to coat bottom and add yellow onions; season with kosher salt. Set skillet over medium heat and cook onions, stirring occasionally and making sure to scrape bottom of pan, until very soft and deep golden brown, 15–20 minutes. Add garlic and cook, stirring occasionally, until onions are caramelized and deeply browned, 25–30 minutes (if any pieces get super dark and stick to the pan, a few drops of water should dislodge them). Let cool.
Step 4
Brush mustard over chilled dough, then sprinkle with cayenne. Stir cheese into caramelized onion mixture and spread across crust in an even layer.
Step 5
Using a mandoline or very sharp knife, thinly slice both squashes crosswise. Cut sweet potato and red onion in half lengthwise, then thinly slice crosswise with mandoline. Arrange vegetables in concentric circles, with rounded edges facing up, starting from the outside edge, leaning slices against the crust, and working your way inward. Drizzle remaining 2 Tbsp. oil over vegetables and season with kosher salt.
Step 6
Bake tart until edges of vegetables are browned (a few spots may even get deeply browned) and crust is golden brown, 75–90 minutes.
Step 7
Melt thyme and butter in a small saucepan and cook just until butter is bubbling. Brush over tart with a pastry brush and sprinkle with sea salt.
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Reviews (123)
Back to TopI don't mind scooping flour into a cup. What I do mind is someone who is bothered by something grouping everyone else into their hissy fit.
Anonymous
Caiforia
1/19/2024
ONCE AGAIN PETITIONING BA TO USE FREAKING GRAMS! NO ONE WANTS TO SPOON FLOUR INTO A CUP
Anonymous
12/22/2023
This was a hit! I followed the recipe exactly, except used goat’s cheese. The amount of sliced vegetables required was enough for me to make two tarts. I used a silicone 12-inch pan and it worked perfectly. I wouldn’t recommend this for a dinner party where you have limited time. It requires some time and finesse.
Anonymous
London
11/24/2023
This was delicious and everyone was blown away by it. The flavors were perfect together and it came together effortlessly. It was so beautiful nobody believed it was so simple to make and they were less convinced of the ease after tasting it!
Bekki
Greeley, Colorado
10/27/2023
Yum yum yum yum yum! The squash and onion/mustard combo is fantastic. I added a little celery root and will add a little Fennel - just a tad - next time. To speed up the prep, I used a frozen 9" pie crust - so technically not a tart. What I loved about this recipe is the edges of the squash and root vegetables crisp up and are chewy when you eat them. That texture, combined with the caramelized onions and the flaky pie crust gives you a really interesting bite - and the mustard is the final burst of YUM. Very satisfying to eat. The prep was not that bad. Will definitely make again - and aim for that 30 mins suggested by another reviewer.
SDeBow
10/9/2023
The first time I made this it took me a while, but with practice you can get it down in 30 minutes, especially if you use a store-bought pie crust. No shame in that! I have made this a dozen times and it's always a hit.
Emily in DC
Washington, DC
3/21/2023
Lots of work but very much worth it. Showstopper and very tasty.
Bonnie
Brookline, MA
1/29/2023
This recipe is very involved. Takes all day, and the payoff is just not enough for the effort. It’s good but should be amazing!
Anonymous
Toronto
12/26/2022
I thought this was going to be hard but it wasn't, and we followed the recipe word for word with the exception of substituting delicata for kabocha (because our local groceries were sold out of delicata.) This was great, looked stunning, and I will make it again. The caramelized onions/cheese situation was ridiculously tasty, as was the dijon mustard. The one thing I'll change next time we make it is slicing the veggies thinner and cooking a little shorter than we did (because the veggies will be thinner and not need as long to cook.) There were a couple pieces of kabocha that had super tough rinds and got a little dry, but other than that this was extremely tasty. Like many other reviewers, we had a ton of squash left over but I wonder if, sliced thinner, I'd be able to layer more into the crust. The extra squash was a fun bonus because we just roasted it in a sheet pan later and bam - easy dinner.
Squash Your Fears
Los Angeles, CA
12/19/2022
Made this on Thanksgiving Day this year. It was really easy, and I'm planning on making it again for Christmas. I followed the instructions precisely other than totally forgetting the delicata squash. whoops! My husband doesn't like winter squash, nor sweet potatoes, but he tried the base, with the onion and the crust, and loved that. Soooo, it's inspired me to try a beet, carrot and red-skin potato variation on the topping, to replace the squash and sweet potato.
Kimber
Seattle, WA
11/29/2022
Love this recipe. But after making it twice following the recipe ive now modified it to my tastes and to speed up the preparation. 1) for the crust I use bread flour it makes a much crisper crust. I also make the dough using my food processor, add flour then cold or frozen butter cubed Pulse until butter is pea sized, dump mixture into a bowl and gently mix in water until it forms a dough. Fridge over night or at least 2 hours before rolling. Once in the tart pan I refrigerate another hour why finishing the prep. 2) don't skip the slow caramelized onions, 3) I use goat cheese, and mix it into the onions while warm, not hot and the cheese w melts perfect. I also add the mustard. And pepper at this point and mix together with onion. 4) with the squash a skip the sweet potato and only use 2 squashes. Using a mandolin I thin slice the squash and onion. After slicing I toss each squash and the onion in xvo, salt and pepper before layering on the onion mixture. 5) I cook on 375' for 60 mins, them brush with thyme infused butter and sprinkle more salt and pepper on top before finishing in the oven for another 30mins, Allow to cool 10mins before cutting. Eveyone I've ever served this to has raved about how good this recipe is, 100% show stopper and a keeper Full disclosure I'm not a home cook,.
Adam
Charleston, SC
11/24/2022
I made this tart for thanksgiving last year (with gluten free flour) and everyone loved it and I think a lot of people were shocked by how much they enjoyed it. I’m making it again tonight, and we’re all so excited to have it again!
Isabel S
Boston, MA
11/23/2022
I have just made this tart for the second time. I think the first was three years ago pre Covid for a big Thanksgiving lunch. It was the star of the show and voted the most successful and prettiest dish. I don't have a mandolin! Why I don't know as the slicing of the squash takes some toll on the joints! But all worth it. No Delicata Squash to be found this year so I have used Kabocha and Butternut. + the sweet potato and red onion. This is a two day effort as I made the pastry the day before. But you definitely need a deep spring clip pan as the fluted ones are not deep enough for the cheese and onion base. Looking forward to Thursday and the compliments. 16/11/22
Anonymous
New York
11/22/2022
First time making this, took 5 hours beginning to end. Hand peeled all squash and potato- wish I could add pictures. This came out amazing and was beautiful. Brought it to a work party and it was the celebrity. My arm was sore from the hand peeling but it gave the thin slices needed.. I used a spring form and just folded over the excess dough and pinched it. It was absolutely perfect in every aspect.
Anonymous
11/17/2022
A warning for those folks who make this for vegetarian friends, and use premade crust: Pillsbury and just about any big-name-brand premade crust uses lard as the fat. It isn't vegetarian friendly. There are small brands that are vegetarian, but they use palm oil, which has other problems ethically. Making your own crust can remedy these problems. I'm about to make this again, and I'm going to try goat butter instead of cow butter, as the coconut oil didn't work as a fat source in the recipe.
Cyr
Vancouver, Canada
11/16/2022