Vegetarian Christmas Quiche

A perfectly festive vegetarian quiche full of Christmas flavors! With a puff pastry crust, dollops of brie and cranberry sauce with a savory mushroom and sweet potato filling, it just feels so special for the holidays. It would be a great addition to a Christmas party menu, or a vegetarian main dish for a festive dinner.

We are in the midst of a festive food takeover here, and loving it! We’re combining some festive treats to make a delicious quiche that feels right for the season. Herby, buttery, sauteed sweet potato and oyster mushrooms (you can use normal mushrooms no problem!) are filling, savory and, in the case of the mushrooms, kind of “meaty”. Brie and cranberry sauce give an extra festive spin to things.

The quiche is baked on a flaky puff pastry crust, which is a double win because 1) the flaky crust feels extra party-ready and 2) it’s just easier to work with than shortcrust pastry so YAY. I’ve made no real effort to tame the overhang, it just puffs up in quite a lovely way and is nice to eat, even if it does initially look a bit different? rustic? Whatever it is, I like it.

This would make a lovely option for a Christmas brunch or party, or a special meal around Christmas time such as Christmas Eve or Boxing Day dinner.

And while you can go fairly luxurious with your ingredient selection, you can also go fairly low budget, because it’s 2022 and the price increases at the supermarket can be a little bit of a buzz kill this Christmas, can’t they?

Ingredient & Substitution Notes

• This crust is made with puff pastry, as we have already discussed, though you can easily swap in shortcrust if you prefer.
• Sweet potato cubes could be swapped for butternut squash. Cooking time would be similar.
• I enjoyed oyster mushrooms in this, but you don’t need to use those. Plain, cheap button or chestnut mushrooms would be fine. It doesn’t have an overly “mushroomy” taste, but if you wanted it to, and had the budget, you could look at some more exotic mushrooms such as chanterelles or porcini.
• I’ve called for herbs de Provence which is just a mix of dried herbs I particularly enjoy. If you don’t have this, a mix of thyme, rosemary and sage will never let you down.
• Let’s talk cheeses: The brie does not need to be fancy here, it’s just one element among many so you can low budget if that suits you. And for the cheese that goes into the egg custard, I’ve given you the option of gruyere OR cheddar. The former is certainly more authentic for a quiche, and it’s always got an edge over cheddar. But I tested it with a mature cheddar, and it turned out well enough that I don’t feel any great need to pay gruyere prices.
• Shallots could be swapped for red or white onion, no stress, just slice them nice and fine.

This quiche is simple to make, but takes around an hour

Sauteeing the sweet potato and mushroom can take around 15 minutes, though if you have a good nonstick pan you don’t need to be actively standing over it and can just let it sit, turning every so often, and multi-task some of your prep at the same time: grating cheese, whisking eggs, etc.

Because the pastry is not blind baked, we want to cook the quiche on a low temperature for a little longer, in order to get the bottom properly cooked without the exposed edges getting burned. For me this was about 30 minutes in the oven, at 160C / 320F (note that my oven is fan forced, so you go a little higher if yours is not).

I’d suggest just keeping an eye on it while cooking, checking in regularly from 25 minutes, because all ovens are different.

Leftovers?

Anything with pastry is never going to be as good reheated, but it’s still very tasty, so don’t hesitate to refrigerate or freeze your leftovers!

To reheat, I’d suggest placing in a warm oven or air fryer to allow the pastry the chance to come back to life a little, though the crust may be overdone by the time the filling is warmed through, so there’s a compromise to be made there. If you microwave it, the pastry will be a little sad, but it’s still very enjoyable.