Leftover Beef Wellington Sandwich
This sandwich is the best way to serve leftover beef wellington! Inside a toasted bun, there's garlic mushrooms, gravy, béarnaise sauce & leftover beef.
Servings: 4 Sandwiches
Equipment
- Large Frying Pan
- Ovenproof Dish
- Mixing Bowl
- Saucepan
Ingredients
- 4 Burger Buns (See Notes)
Beef Wellington
- 2 Thick Slices Of Leftover Beef Wellington (See Notes)
- 300 g Gravy
Béarnaise Sauce
- 100 g Unsalted Butter
- ½ tbsp White Wine Vinegar
- 25 g Egg Yolks
- ½ tbsp Lemon Juice
- 1 tbsp Finely Chopped Tarragon
Garlic Mushrooms
- 250 g Chestnut Mushrooms
- 1 tbsp Vegetable Oil
- 3 Garlic Cloves
- A Knob Of Butter
Instructions
Beef Wellington
- Preheat an oven to 180°c/160°c fan (356°f/320°f).
- Cut each slice of beef wellington in half then place into an ovenproof dish. Spoon gravy over each slice then cover the dish with foil. Bake in the oven for 10-15 minutes, until hot.
Béarnaise Sauce
- Place the butter into small saucepan then cook over a low heat, until melted. Pour into a jug then set aside.
- Next, place the vinegar & yolks into a heatproof mixing bowl, whisk to combine then set over a pan of barely simmering water. Make sure the bottom of the bowl isn't touching the water.
- Gently cook the egg yolks, whisking constantly until the mix is thick enough to coat the back of a spoon. This will take 2-3 minutes.
- Take the bowl off the heat then slowly pour in the melted butter, whisking constantly, to emulsify. If the sauce seems a little thick, whisk in some of the milk solids from the bottom of the jug as well.
- Whisk the lemon juice & chopped tarragon into the sauce then season with salt & pepper, to taste. Set aside for now.If the béarnaise sauce has thickened up too much when you go to serve it, whisk in a splash of warm water.
Garlic Mushrooms
- Place a large frying pan over a high heat. If you'd like to toast your burger buns, cut them in half & toast them now, in the dry frying pan.
- Next, add the tbsp of veg oil into the pan & leave to get smoking hot. In the meantime, thinly slice the mushrooms & grate the garlic. Set the garlic to one side.
- Add the mushrooms into the pan, season with salt then fry until golden & crisp, tossing the pan regularly.
- Add the garlic & butter to the mushrooms, cook for another minute then season with freshly cracked black pepper.
Assembling The Sandwich
- Divide the garlic mushrooms between each bun then top with the warm beef wellington, the gravy & a generous amount of béarnaise sauce. Place the top part of each bun on top then serve straight away.
Notes
1. Cooking On An Aga - Reheat the beef wellington in the baking oven, on the bottom set of runners. Use the simmering plate when making the bearnaise & fry the mushrooms using the boiling plate.
2. Beef Wellington - You'll need two thick slices of beef wellington for this sandwich. There's half a slice in each bun! I'd recommend using leftovers from our beef wellington recipe
3. Burger Buns - I used my potato burger buns for this sandwich but any good burger bun will work.
4. Béarnaise - Béarnaise sauce is best served warm, so can't really be made in advance. Feel free to add in more tarragon if you'd prefer a stronger flavour.
5. Gravy - I reheated my beef wellington with my homemade red wine gravy. Feel free to use a different gravy if you'd prefer.
6. Mushrooms - Pretty much any type of mushroom can be used for this sandwich. I used chestnut mushrooms but button or portobello would be some other good options.