Keto Beef Wellington with Mushroom Duxelles and Almond-Flour Pastry

Ingredients

1. 700 g grass-fed centre-cut beef fillet, trimmed
2. 6 g fine sea salt
3. 1 tsp black pepper, freshly cracked
4. 15 ml avocado oil, for searing
5. 1 tbsp Dijon mustard (no added sugar)
6. 300 g organic chestnut mushrooms, very finely chopped
7. 20 g organic shallot, finely chopped
8. 1 tsp thyme leaves
9. 20 g organic butter, for the duxelles
10. 80 g prosciutto, thinly sliced
11. 150 g almond flour
12. 170 g low-moisture mozzarella, grated
13. 30 g full-fat cream cheese
14. 1 piece organic egg, for the pastry
15. 1 piece organic egg yolk, beaten with 1 tsp water, for the egg wash

Step-by-step method

1. Sear the fillet. Pat the beef very dry and season all over with salt and pepper. Heat the avocado oil in a heavy pan until it just smokes and sear the fillet on every side, ends included, about 1 minute a side, 5 minutes in all. While it is still hot, brush it all over with the Dijon and leave to cool.
2. Make the duxelles. Melt the butter in a wide pan, add the shallot for 1 minute, then the mushrooms and thyme. Cook over medium-high, stirring often, until every drop of liquid has evaporated and the mushrooms have become a dark, dry paste, 12–15 minutes. Season and cool completely.
3. Wrap in prosciutto. Lay the prosciutto slices, overlapping, on a clean, lightly dampened linen tea towel in a rectangle big enough to enclose the fillet. Spread the duxelles evenly over it, set the beef on top and use the towel to roll it up tightly. Chill in the towel for 20 minutes to firm.
4. Make the pastry. Melt the mozzarella and cream cheese together in a bowl over simmering water, stirring until smooth. Stir in the almond flour and the egg and knead to a smooth dough. Roll it out on a lightly oiled stone or steel worktop with an oiled rolling pin to a rectangle about 4 mm thick; if it sticks, chill it for 10 minutes.
5. Encase. Unroll the beef onto the pastry and wrap it snugly, trimming the excess and pressing the seam closed underneath. Set it seam-down on a buttered enamelled or cast-iron tray, brush with the egg wash, score a light crosshatch and chill for 10 minutes. Heat the oven to 200 °C / 400 °F (fan 180 °C).
6. Bake. Bake until the pastry is deep golden and a thermometer in the centre reads 50 °C / 122 °F for medium-rare, 25–30 minutes; if the pastry browns too fast, lower the oven to 180 °C. It will coast up a few degrees as it rests.
7. Rest and carve. Rest for 10 minutes so the juices settle, then slice into thick rounds with a serrated knife, each one showing the pink fillet, dark duxelles ring and golden crust.

Variations

• Weigh substitutions and recalculate nutrition before serving.

Storage

Best served fresh. Refrigerate leftovers promptly in a covered container and use within two days.

Questions and answers