The former was sent off a short priced 2-5f to follow up her maiden win over course and distance last month. For most of the race, everything seemed to be going to plan, as the Willie Mullins trained mare cut out the running under jockey Paul Townend.
From three out, only the Henry De Bromhead trained Birdie Or Bust presented any sort of meaningful challenge. However, on the run to the final flight, Fun Fun Fun looked in full control as she asserted from that J.P. McManus owned rival.
Having jumped the last in front, Fun Fun Fun then appeared to take a stumble a couple of strides after the obstacle, in the process losing all momentum. That allowed Rachael Blackmore to come through aboard 7-2 chance Birdie Or Bust, staying on to win by three-and-a-quarter lengths.
Winning trainer Henry De Bromhead said: "Obviously we got a bit of luck but she ran really well and we were delighted with her. She definitely wasn't herself in the north the last day but looked back to herself today with the way she jumped and travelled. She didn't seem herself in Down Royal.
"We will get her home and see what everyone would like to do. She has options and is lovely mare."