Place the Picanha with the fat side on a cutting board. Insert a long sharp knife into the side and push in deeply. Put your hand on the Picanha and cut towards the middle until you are 3 cm from the edge on the other side. There is now a hollow. Turn the Picanha inside out (a bit like a pillow case turned the wrong way round), so that the fat side is on the inside. Fill the cavity with the pepper, manchego and chorizo, and close the Picanha with skewers. Grease the Picanha well with oil, sprinkle generously with salt and black pepper and place it on the grill above the plate setter. The Bastard above the plate setter. Close the lid and cook for about 20 minutes until a core temperature of 48 degrees. Serve the Picanha in thick slices.