Slightly drizzle the Flank with truffle oil from both sides, season to taste with salt flakes (we used Maldon Sea Salt Flakes) and rub in well.
Prepare your Big Green Egg for indirect heat and cook the flank for about 20 minutes at 150°C / 300°F until an internal temperature of 50°C / 122°F is reached.
Remove the conveggtor and oil the cast iron grid. Open all vents to reach a very high temperature and sear the Steak for 90 seconds on each side and turn for 90° after 45 seconds to ensure a proper branding.
Let the me.at rest for about 5 minutes, season to taste with pepper and cut into thin slices against the me.at fibres.