When James and Joanna Fennell opened the doors of the Green Barn restaurant on the grounds of their family home at Burtown House for the first time in late 2016, it was the realisation of several years of hard graft to bring the Co Kildare estate back to life. The pair, a photographer and designer respectively, went all-in on the family property in Athy in the 2010s, living in a converted stable for six years while doing up the Georgian villa. To bring in some extra income during this period, they opened up 12 acres of gardens that James Fennell’s…