A mushroom Wellington is a vegetarian Thanksgiving main made of sautéed mushrooms and herbs wrapped in puff pastry and baked until the pastry is golden. The most important step is cooking the filling until it is dry, so the pastry stays crisp. It is a strong centerpiece if you are planning Thanksgiving alternatives to turkey or a vegetarian Thanksgiving dinner. See the Thanksgiving guide and Thanksgiving mains, diets and leftovers.
Cook the filling until it is dry
Finely chop about 2 pounds of mixed mushrooms. Cook them in a wide skillet with a little oil or butter, plus minced shallot or onion, salt, pepper, and thyme, until the mushrooms have given off their liquid and that liquid has cooked away. The mixture should look jammy, not wet. Stir in a spoonful of Dijon mustard or a splash of soy sauce for depth, then cool the filling completely. You can do this a day ahead and refrigerate it. A chilled filling is easier to wrap and is less likely to melt the pastry.
Wrap, chill, and bake
Roll a sheet of thawed puff pastry just large enough to wrap the filling. Pile the mushrooms into a tight log, wrap, and pinch the seam closed on the bottom. Brush with beaten egg, cut a few small slits in the top, and chill the wrapped loaf for at least 20 minutes. Bake at 400°F on a parchment-lined sheet pan for about 35 to 45 minutes, until the pastry is deep golden. Rest 10 minutes before slicing. Serve with vegan gravy or gluten-free gravy if that fits the table. Use gluten-free stuffing as a side if you need a wheat-free plate; standard puff pastry contains gluten.
Make-ahead and serving notes
The filling can be cooked up to a day ahead, which actually helps because it must be cold before it meets the pastry. You can also wrap the loaf in the morning, keep it chilled, and bake it in the afternoon so it comes out just before dinner. If the pastry browns too fast, tent it loosely with foil. Slice it with a serrated knife so the layers do not crush. Leftovers keep 3 to 4 days in the refrigerator and reheat best in a 350°F oven, not the microwave, so the pastry can crisp again. It is rich, so a sharp salad or a simple vegetable side is plenty beside it.
Frequently asked questions
Can I make mushroom Wellington ahead?
Yes. Cook and cool the filling a day ahead. You can also wrap the loaf and refrigerate it for several hours before baking. Add a few extra minutes in the oven if it goes in cold.
Why is my pastry soggy?
The filling was probably still wet, or it was wrapped while hot. Cook the mushrooms until their liquid evaporates, cool them fully, and bake on a hot oven rack until the pastry is deeply browned.
Is mushroom Wellington vegan?
Not automatically. Many puff pastries contain butter, and some fillings use butter or egg wash. Use a vegan pastry and oil, and skip the egg wash, if you need a vegan version.
Helpful kitchen tools
- HVH 9×13 Ceramic Baking Dish Set — A sturdy dish can hold the baked Wellington for serving, or roast vegetables beside it.
- OXO Good Grips Bent Icing Spatula — Helpful for sealing the pastry seam and transferring slices.
- Pyrex Deep 9×13-Inch Glass Baking Dish with Lid — A lidded dish is useful if you chill the wrapped loaf before baking.
- Stasher Silicone Reusable Food Storage Bags, 4-Pack — Good for storing leftover slices without crushing the pastry.
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