Preheat oven (electric cooker: 200 °C/circulating air: 180 °C/gas: see manufacturer). Line a baking tray with baking paper. Cut the top of the buns twice lengthwise and three times crosswise, but do not cut through (this creates a 12-part grid of buns). Cut herb butter into thin slices, cut cheese into small pieces. Carefully bend the rolls apart slightly. Put butter first, then cheese into the incisions.
Place the rolls on the tray. Bake in a hot oven for about 12 minutes until golden brown. Wash the chives, shake dry and cut into fine rolls. Sprinkle the rolls with them and serve hot.