“The coals should be grey and glowing nicely, and evenly distributed so that you get about 20 minutes of good even heat,” he adds. “Oil the grill well with a kitchen towel or paper and make sure it’s clean. Use a digital thermometer to measure the internal temperature of the meat. You want to pull the burgers when they are around 52C, put them on a plate and tent them with foil, and let them rest for about five minutes.”