Butternut squash or mushrooms? For this extra-creamy veggie quiche, it’s your choice

Joe Yonan tests out Jamie Oliver’s clever method

Using butternut squash will give the quiche a lighter flavour (Laura Chase de Formigny/The Washington Post)

I can’t tell you the last time I made quiche. It’s not that I don’t like it – a good one, eggy and creamy and light, with a flaky crust – is a thing of beauty. But when I’m in the mood for savoury baked egg dishes, I’m more of a frittata cook, loving how adaptable and no-fuss that dish can be.

But my pie-baking itch flares up every holiday season, and a quiche is really nothing more than a savoury pie (or tart), so when I saw Jamie Oliver’s recipe for what he simply called vegetable quiche in his new book Together, I took a closer look. Oliver offers two options in this recipe – one for butternut squash and one for mushrooms – and rather than incorporating either in chunks in the filling, he has you puree the cooked veg with the requisite eggs, cream and cheese before baking.

I’ll confess: this is not a typical recipe for this column, because it takes too long to be feasible on any given weeknight. But that’s only if you make it start to finish. Instead, you can divide up the work as you see fit: one option is to make the simple pastry one night, cook the filling on another and bake the quiche on the third, refrigerating your work in between.

When it comes to that pastry, Oliver’s recipe includes a technique I’ve been meaning to try after seeing it on countless episodes of The Great British Baking Show. After you lay the pastry into the tart pan, instead of cutting off the excess before baking, you leave it on, pressing it over the edge of the pan and letting it hang, and blind-bake it that way (without the filling, and with pie weights to hold everything in place). Once it cools, you use a sharp paring knife to cut the pastry off flush with the edge of the tin.

The brilliant thing about this method is that it helps prevent shrinkage – something that seems to always afflict my tart crusts, even if I’m careful to chill the dough and to resist stretching it. Since this quiche uses a generous amount of filling for the final bake, any shrinkage would render the tart too shallow to hold it all. Trust me, I tried it both ways, and I’ll never go back.

Because the quiche is on the denser side, it boasts a super-creamy texture approaching that of a savoury cheesecake. It also takes a little longer to cool – and might even taste better cold than warm, making this a great option not only for holiday or other nice dinners or brunches but for leftover lunches, whether you’re brown-bagging it or not. I’m already imagining saving the idea for warmer weather, when it would make an outstanding picnic item.

In case you’re wondering which way to go here – squash or mushroom – let me describe the differences, beyond the obvious colour. The squash is a touch denser, given the starchiness of the starring vegetable, but with a lighter flavour. The mushroom ends up a little lighter in texture but deeper in flavour, almost like a faux liver pâté. If you’d like, saute a few mushroom slices for the garnish, just to signal to your guests what’s inside – or let them taste and have a guess.

Creamy butternut squash or mushroom quiche

Mushrooms are deeper in flavour, but even lighter (Laura Chase de Formigny/The Washington Post)

Serves: 12

Active time: 1 hour | Total time: 3 hours

Make ahead: Tightly wrap and refrigerate the pastry dough for up to 5 days or freeze for up to 3 months. Refrigerate the baked tart shell for up to 2 days. Refrigerate the filling for up to 5 days. Refrigerate the assembled, baked and cooled quiche for up to 3 days.

Storage notes: Refrigerate leftovers for up to 3 days.

Ingredients:

205g all-purpose flour, plus more for dusting

9 tbsp (128g) cold unsalted butter, cut into small pieces

½ tsp fine salt, divided, plus more to taste

120ml cold water, divided, plus more as needed

800g butternut squash or mixed mushrooms

1 tbsp plus 1 tsp extra-virgin olive oil, divided, plus more for greasing

170g yellow onion, thinly sliced

4 garlic cloves, thinly sliced

6 large eggs

7 tbsp heavy cream

113g cheddar cheese, coarsely grated

60g crumbly goat cheese

2 fresh thyme sprigs

Method:

Lightly flour your work surface.

In a food processor, combine the flour, butter and ¼ teaspoon of salt, and pulse until the mixture resembles coarse breadcrumbs. Add 60ml of the cold water and pulse for a few more seconds until the dough just starts to come together, adding more water, 1 tablespoon at a time, if needed. Transfer the dough to the work surface and push and pat (without kneading) into a round. Wrap it in plastic or beeswax wrap and refrigerate for 30 minutes.

Prep your chosen vegetable: Peel, carefully halve and seed the squash, then cut into 2cm chunks. Or clean, trim and slice the mushrooms (removing and composting the stems if you use shiitakes).

In a large frying pan over medium heat, heat 1 tablespoon of the oil until it shimmers. Add the onion, garlic and remaining ¼ teaspoon of salt and cook, stirring frequently, until the vegetables start to soften, about 3 minutes. If using squash, add it along with the remaining 60ml of water, reduce the heat to medium, cover and cook, stirring occasionally, until the squash is very soft, 20 minutes. Uncover, increase the heat to medium-high, and cook, stirring, until the extra water has evaporated, 2 to 3 minutes. If using mushrooms, cook uncovered over medium-high heat, using tongs to toss frequently, until they wilt, then reduce the heat to medium and cook, stirring and scraping the bottom of the pan occasionally, until they are soft and starting to brown, 20 minutes. Taste, and season with more salt as needed. Turn off the heat and let cool.

Position a rack in the middle of the oven and preheat to 220C. Lightly oil a 25cm quiche pan with a removable bottom.

Roll out the pastry on the flour-dusted surface until it's about 35cm in diameter and just under 0.5cm thick. Gently roll it up around the rolling pin, then unroll it over the oiled pan and ease it into the sides, curling the excess pastry tightly over the edges. Prick the base all over with a fork, top with a sheet of parchment paper and fill with coins, beans or other pie weights. Transfer to a large, rimmed baking tray and bake for 15 minutes, or until the pastry is set, then remove the paper and weights and continue baking for about 10 minutes, or until lightly browned and firm. Cool, then use a sharp paring knife to trim off the excess pastry.

Transfer the squash or mushroom mixture to a blender. Add the eggs, cream and cheddar and puree until smooth.

Pour or scrape the filling (the mushroom will be thicker than the squash) into the baked and cooled pastry shell, being careful not to overfill (you may have a little squash filling left over; feel free to pour it into a ramekin or two and bake alongside the quiche). Crumble over the goat cheese. Rub the thyme sprigs with the remaining 1 teaspoon oil, then pick the tips and leaves over the quiche.

Bake for about 40 minutes, or until the quiche is set in the centre (it should feel firm to the touch, with little to no wobbling). Transfer to a cooling rack and let cool in the tart pan for at least 30 minutes, then unmold and serve warm, or let cool completely, refrigerate, and serve cold (if you want to prevent the quiche from cracking, you can leave it in the oven to cool, turning off the oven and opening the door slightly).

Nutrition information per serving (1 slice)

Using squash: calories: 311; total fat: 20g; saturated fat: 11g; cholesterol: 141mg; sodium: 225mg; carbohydrates: 23g; dietary fibre: 2g; sugar: 2g; protein: 9g.

Using mushrooms: calories: 296; total fat: 21g; saturated fat: 11g; cholesterol: 141mg; sodium: 226mg; carbohydrates: 18g; dietary fibre: 1g; sugar: 2g; protein: 11g.

This analysis is an estimate based on available ingredients and this preparation. It should not substitute for a dietitian’s or nutritionist’s advice.

Adapted from ‘Together’ by Jamie Oliver (Flatiron Books, 2021).

© The Washington Post