At Christmas time in 2021, Sam Dennigan reluctantly headed to meet a chef with an idea at The Long Hall on George’s Street. Dennigan had made his name through the creation of plant-based frozen food business Strong Roots, which had just welcomed a $55 million investment from Canadian giant McCain at the time. But he was sceptical about the viability of the notoriously taxing restaurant business. It was Daire Hickey, the co-founder of 150Bond, the communications firm that aided in Strong Roots’ US expansion, who convinced him to go. “Daire wanted to introduce me to this chef, and I was…