A deliciously rich Mushroom Wellington with chestnuts, spinach, caramelized red onions, and crispy puff pastry. This is perfect for a festive dinner or as a showstopper for a vegetarian Christmas dinner. Packed with flavour and easy to make, your guests will love this!
Whether you’re having a Vegetarian Christmas or you have veggie friends visiting over the Christmas period this Mushroom Wellington has you covered. It’s rich and filling, packed with flavour and so easy to make!
A delicious filling of sautéed garlic and tarragon mushrooms, with caramelized red onions, chestnuts and spinach. All enclosed in a crispy golden puff pastry! This is such a tasty dish, even meat-eaters will love this!
But first, What is a Beef Wellington?
Beef Wellington is an indulgent dish of beef, usually fillet, covered in a mixture of mushrooms, herbs and sometimes foie gras, baked in pastry. The origins of beef wellington are sketchy, from the French speciality filet de bœuf en croûte to the Duke of Wellington. With some believing it to be a 20th-century dish. However what is clear is that it is very much a celebratory, showstopper dish.
What Goes in a Vegetarian Wellington?
- Mushrooms – I tend to choose chestnut/brown mushrooms for this, but you can use a mixture of wild mushrooms with the chestnuts.
- Red Onions – These are perfect for caramelising which brings a lovely sweetness to this dish.
- Spinach – Baby spinach is best for this, I use fresh spinach but you could use frozen too is you prefer.
- Chestnuts – These add a lovely festive flavour to this mushroom wellington with the added bonus of bulking up the filling too. Store-bought ready-cooked is perfect.
- Tarragon – this versatile herb has an intense flavour, so a little goes a long way. It has a unique taste of sweet aniseed and mild vanilla. If you can’t find tarragon then fennel seeds may work instead. Fresh tarragon is best for this recipe.
- Pastry – Puff pastry works best here, I always use a store-bought, pre-rolled pastry.
How to Make Mushroom Wellington
- Start by caramelizing the onions, heat the oil in a pan add the onions with a little salt then cook until the onions are soft, at least 15 minutes. Then add the balsamic vinegar and stir well. Leave the onions to cool in a large bowl.
- Next, sauté the mushrooms. Heat the butter in a pan and cook the mushrooms until they have released all their juices. Now, add the garlic and tarragon and cook for a minute or two. Finally, turn up the heat a bit and add the red wine, cook, until almost all of the liquid has evaporated. Finally, crumble in the chestnuts and mix well. Transfer to the bowl with the red onions.
- Cook the spinach. Heat a little oil in a pan and cook the spinach until wilted. Then chop it finely.
- Combine the filling. Add the spinach to the bowl along with the mushrooms and red onions. Add a couple of tablespoons of fine breadcrumbs, a generous seasoning of salt and pepper and mix well.
- Make the wellington. Roll out the pastry then spread the mushroom mixture along the centre of the pastry. Fold over one side, brush with egg wash then fold over the other side. Fold up the ends then carefully turn the wellington over.
- Finishing touches. Using a very sharp knife score the pastry into diamonds then brush with egg wash. Bake until golden brown.
Top Tips for Making the Best Mushroom Wellington
- Cook the red onions until the are really soft, the longer the better, but if you are short on time 15 minutes will work. Keep an eye on them, stir them often and don’t let them burn.
- Wipe or dry brush the mushrooms clean, mushrooms take in every drop of liquid, you don’t want soggy mushrooms.
- Do yourself a favour and buy the pre-cooked chestnuts. I roasted chestnuts once and once only!
- Same goes for the puff pastry, store-bought is totally acceptable. Go for a pre-rolled all-butter puff pastry. This will save you so much time.
- Leave the filling to cool before you place it on the pastry. A warm filling will heat up the pastry, make it soft, and very hard to work with.
- Make sure your pastry is at room temperature, and make sure your hands are cold. All this will help with handling the pastry.
- If you want a golden pastry don’t skip the egg wash. Be generous with it and brush the sides as well as the top.
- Leave the wellington to cool slightly before removing it from the baking sheet. It will be easier to lift off once it has cooled a little.
How to Serve Mushroom Wellington
If we’re having this for Christmas dinner then I will serve this with all the trimmings, roast potatoes, roasted carrots and parsnips Brussel sprouts, gravy and cranberry sauce. If we have this for Sunday lunch I serve it with creamy mashed potatoes and broccoli.
Can I Make This Ahead?
Yes! This is great for making ahead of time. You can make the filling a day or two in advance, just keep it covered in the refrigerator until you are ready to use it. You can make the entire dish a day ahead, just don’t egg wash it. Keep in in the fridge until you are ready to bake it, remember to egg wash it before you bake it.
Can I Freeze this Mushroom Wellington?
Yes, you can. Freeze the completed dish before you bake it. Bake it from frozen, but please note it may take longer to cook and there may be some difference in the consistency of the filling.
Can I reheat this?
Yes, although this is really best eaten fresh from the oven. You can keep any leftovers in the fridge for up to two days. I had the best results by placing the pie in a dish covering with foil and heating for about 30 minutes until the filling is piping hot. I remove the foil about 10 minutes before the end of reheating so as the pastry doesn’t get soggy.
More Festive Recipes:
- Nut Roast en Croûte
- Stuffed Squash with Wild Rice
- Vegetarian Sausage Rolls
- Beetroot and Goat’s Cheese Tart
Have you made this Mushroom Wellington Recipe? Rate it and leave me a comment below to let me know what you think!
- 1 medium red onion (150g) peeled, cut in half lengthways and sliced
- 1 1/2 tbsp olive oil divided
- 1 tsp sea salt divided
- 1/2 tsp freshly cracked black pepper
- 1 tbsp balsamic vinegar
- 1 tbsp butter
- 280 g chestnut/brown mushrooms (approx 4 cups) wiped clean then sliced
- 4 cloves of garlic minced
- 1 tbsp fresh chopped tarragon
- 1 tbsp red wine optional
- 100 g cooked chestnuts (approx 3/4 cup)
- 100 g baby spinach ( approx 3 1/3 cups)
- 3 tbsp fine breadcrumbs
- 1 x 320g sheet of puff pastry
- 1 medium egg beaten
- Preheat the oven to 190C/ 374F.Line a baking tray with parchment paper.
- Heat 1 tablespoon of olive oil in a frying pan. Add the onions with 1/4 teaspoon of sea salt and cook over medium heat until soft. At least 15 minutes. 20 - 25 minutes if you have more time.Once soft add 1 tablespoon of balsamic vinegar and stir well until the liquid evaporates.Remove to a large mixing bowl and leave to cool.
- Heat 1 tablespoon of butter in a large sauté pan. Add the mushrooms and cook until they are soft and they have released their juices. Add 4 minced cloves of garlic and 1 tablespoon of chopped tarragon. Stir well and cook for a minute or two.Turn up the heat then add 1 tablespoon of red wine and stir well. Cook until all the liquid has evaporated.Crumble the chestnuts into the pan and mix well. Remove this mixture to the mixing bowl with the red onions and leave to cool.
- Heat 1/2 a tablespoon of olive oil in a pan, add the spinach and cook until wilted.Drain and squeeze as much liquid out of the spinach as you can. Transfer to a chopping board then roughly chop.Add the chopped spinach to the mixing bowl with the mushrooms.
- Add 3 tablespoons of fine breadcrumbs along with 1/4 teaspoon of salt and 1/4 teaspoon of freshly cracked black pepper to the mixing bowl. Mix everything together well.
- Roll out the puff pastry.Add the mushroom filling along the centre of the pastry and using clean hands shape into a sausage shape.Turn one side of the pastry over the mushroom mixture, brush the egg wash then turn the other side over. Use a fork to seal the pastry. Fold up the ends of the wellington and again use a fork to see them.Carefully turn the welling over so the seal is on the bottom. Using a very sharp knife score diamonds in your pastry. Start by scoring diagonal line in one direction along the whole wellington then repeat in the opposite direction.Brush the whole wellington in egg wash, remembering to do the sides too.Bake in the oven for 30 minutes or until the pastry is golden brown and the pastry is completely cooked.Remove from the oven and leave to cool slightly before transferring to a serving dish or board.
- Pastry - I use a store-bought, ready-rolled puff pastry. All butter puff pastry is great but regular puff pastry works well too.
- Mushrooms - Chestnut or brown mushrooms are my choice of mushrooms for this recipe. However, you can add wild mushrooms here too, just ensure the quantities are the same weight listed in the recipe.
- Chestnuts - I use store-bought pre-cooked chestnuts. If you have a nut allergy you could swap the chestnuts for pre-cooked puy lentils.
- Tarragon - I use fresh tarragon for this dish, if you can't find it then fennel seeds would be a good alternative. Or you could also make this with rosemary and thyme.
- Can I make this vegan? Yes, this is really easy to make vegan. Swap the butter for vegan butter or use olive oil. Swap the puff pastry for a vegan puff pastry and use plant milk instead of egg for the wash.
- Can I make this gluten-free? Yes, use a gluten-free puff pastry and make use gluten-free bread for the breadcrumbs.
- Can I freeze this? Yes, make it until the baking stage then freeze. Cook from frozen. You will need to cook it for longer than the recipe indicates though.
- Nutrition - Nutritional information is approximate and is calculated using an online nutrition tool. It is based on one serving.