Recipe Detail Page

1. For mushroom coating, melt butter in a large skillet. Add shallots and sauté over medium-low heat until softened, about 5 minutes. Do not brown. Add mushrooms. Stir in salt and thyme. Increase heat to medium. Stir often. Once mushrooms release their liquid, after about 5 minutes, stir almost constantly and continue cooking until mushrooms appear dry. This may take another 5 to 10 minutes.
 
2. Turn into a bowl and refrigerate. Mushroom mixture  can be made up to 1 day before using. Keep covered and refrigerated.
 
3. For the beef, measure length and circumference of tenderloin so you will know how large a rectangle of pastry you will need to enclose it, remembering it’ll get slightly larger due to the coating of mushrooms and pâté.
 
4. Rub beef all over with 1 tbsp (15 mL) oil. Heat remaining 1 tbsp (15 mL) oil in a large skillet. Add meat, curving if necessary to fit in pan. Cook over medium-high until browned all over. To ensure entire bottom of roast is in contact with the hot pan, gently press down on meat. Browning will take about 8 minutes.
 
5. Remove to a rack set on a sheet pan and refrigerate at least until cold to the touch, about 2 hours. Loosely cover if leaving longer.
 
6. For pastry, place pastry on a lightly floured work surface. Using a floured heavy rolling pin, roll pastry out to a rectangle large enough to enclose beef. Always roll from the middle toward the edges. You will need a rectangle approximately 4 inches (10 cm) wider than the circumference of the tenderloin and 5 inches (12 cm) longer. Our tenderloin needed a rectangle 13 inches (32 cm) wide and 18 inches (45 cm) long.
 
7. Line a large rimmed baking sheet with parchment. Whisk egg with 1 tbsp (15 mL) water and set aside.
 
8. Heat oven to 400°F (204°C).
 
9. Remove cold tenderloin from refrigerator and place on a piece of waxed paper. Pat dry. Spread half of cold pâté overtop, halfway down the sides and ends of beef. Then pat half of mushroom mixture on top of pâté. Pick up meat, turn over and place into the middle of the pastry, mushroom-coated  side down. Repeat spreading the pâté onto the uncovered side of the tenderloin and patting on the mushroom mixture to cover entire tenderloin. Use any mushroom mixture that falls on the waxed paper to fill in gaps.
 
10. To wrap pastry around beef, bring the long sides together overlapping as necessary to tightly encase meat. Press or pinch this overlap to the pastry underneath. Then press or roll together the pastry overlaps at ends of meat. Trim off excess to use for decorations. Lift ends up and press onto top of tenderloin, forming a compact roll. Pinch these edges onto the pastry underneath.
 
11. Carefully invert wrapped tenderloin onto parchment-covered baking sheet and brush with egg mixture. Make three small slits, about 1 inch (2.5 cm) long, in the top for steam to escape. Or use a small cutter to cut out a hole. To add decorations, roll out pastry trimmings and use cutters to cut out leaves or stars. Brush with egg mixture and gently press onto top of roll around the cut-out area.
 
12. Bake until pastry is golden brown and an instant-read meat thermometer inserted into centre of meat (through one of the slits) registers 115°F (46°C) for rare or 120° (49°C) for medium-rare, about 35 to 40 minutes. Let rest on a cutting board 15 minutes before slicing.