Sweet Potato Wellington

Preheat oven to 180°C. Line a baking tray with baking paper. Place sweet potatoes on tray and rub with 1 tbs oil. Season and bake for 30 minutes or until tender when pierced with a skewer. Set aside to cool.

Meanwhile, finely chop mushroom tops. Place kale in a bowl and cover with boiling water. Stand for 2 minutes to wilt. Drain, rinse under cold water and drain well. Heat remaining oil and 20g margarine in a frying pan over high heat. Add onion and cook for 4 minutes or until soft. Add chopped mushroom and garlic. Cook for 8 minutes or until golden and liquid evaporates. Stir in kale and tarragon. Season to taste and set aside to cool.

Preheat oven to 200°C. Line a baking tray with baking paper. Cut 1 pastry sheet in half. Join one half to each full pastry sheet by overlapping edges and pressing firmly together. Join long sides of both together to form a 48x36cm rectangle. Spoon half the mushroom mixture along the centre, leaving 8cm on each side. Peel potatoes and trim ends. Lay over mushroom and press remaining mushroom mixture onto potatoes. Fold one side of pastry over and roll to enclose. Fold ends under and trim excess. Transfer to tray, brush with remaining margarine and bake for 20-25 minutes or until golden.

Meanwhile, to make the jus, bring stock, reserved mushroom stalks and onion to the boil in a saucepan over high heat. Reduce heat to medium and simmer for 15 minutes or until reduced by one-third.

Mash margarine and cornflour in a small bowl. Gradually whisk into stock mixture. Cook for 2 minutes or until slightly thickened. Strain into a serving jug and discard solids. Slice wellington and serve with jus and steamed vegetables.