Line two baking trays with baking paper.
To prepare the filling, heat the oil in a medium frying pan over low heat. Cook the shallots, until softened. Add the sugar and cook for 3–4 minutes, until they begin to caramelise. Add the blueberries, rosemary, sage and vinegar and cook for 10 minutes, or until the blueberries collapse and most of the liquid has evaporated. Add the panko crumbs and stir to combine. Season with salt and pepper and set aside to cool.
To prepare the pork fillets, using a sharp knife remove and discard the silver skin from the top of the fillets. Tuck the tips of the fillets under, so that both ends of the fillets are roughly the same thickness. Secure in place, tying around with kitchen string once or twice. Drizzle the fillets with oil and rub to coat. Sprinkle with rosemary and season with salt and pepper.
Preheat a large frying pan over high heat, until smoking.
Seal the fillets in the pan, turning frequently, for 3–4 minutes, until browned all over. Transfer onto a tray and set aside to cool. Remove and discard the string.
Place three sheets of the pastry onto a clean kitchen bench. Cut one of the sheets in half. Join one half onto each of the remaining sheets, to make two even sized rectangles. Press down with the twines of a fork along the seam, to secure.
Working with one of the prepared pastry sheets at a time, lay half of the prosciutto slices acrossways, slightly overlapping down the centre to make a strip the length of the pork fillets and leaving a boarder at either end. Spoon half of the blueberry filling down the centreline of the prosciutto and place the pork fillet, tucked side facing upwards, on top of the filling.
Brush the pastry boarder with egg wash. Lift the pastry edges up and over the fillet to wrap and firmly enclose. Turn over and place onto one of the prepared baking trays, seam side facing downwards. Reshape the parcel so the top has a nice curved surface. Flatten the pastry ends downwards and fold in the corners inwards as if you were wrapping a present. Trim off the excess pastry and pinch or crimp the ends to secure. Repeat to make another pork Wellington.
Use the remaining sheet of pastry to cut into strips, leaves, shapes or whatever you fancy for decorating you parcels. You can also skip this step and just leave them plain. Brush the parcels with egg wash and decorate with additional pastry as desired. Brush the decorations with egg wash. Make two or three small incisions into the top of the pastry parcel to allow the steam to escape.
Bake the Wellingtons for 15 minutes, then reduce the oven temperature to 180 °C and cook for a further 15 minutes, or until pastry is puffed and golden brown and pork reads (63–65 °C) when a meat thermometer is inserted into the thickest part. Set aside to rest for 10 minutes. You may need to swap your trays around half way through both cooking times, if your oven is not an even cooking temperature.
To make the horseradish cream, mix the sour cream and horseradish together in a small bowl. Add the lemon juice and season with salt.
Slice each Wellington into three even potions and serve with horseradish cream.
This recipe is much easier then you think! Follow our instructional video.