In 1988 – six years before her first building was made and 24 before becoming a Dame – Zaha Hadid was a "paper architect" living in a small Kensington flat and working in one room of a converted Clerkenwell school, which she got to through the boys' entrance.

"I am seen as a Martian, but it's good to feel displaced," she said, encouraging me to match her consumption of countless espressos, and Marlboros, while examining her commissions, competition entries and sketches. Although she'd later design a "liquid glacial coffee table" (price £100,000), I met her in an environment of inclined drawing boards and no spare surface on which to place a cup. She talked of her childhood in Baghdad, watching Marsh Arabs passing with gemir (buffalo cheese) balanced on their heads, and a trip with her father to Sumeria, where architecture was born 4,500 years ago.

Hadid studied maths at Beirut University but moved to London in 1972 to study at the Architectural Association. She had to rely, she said, on Bayswater as the only source of Lebanese hummus, pitta bread and really strong coffee.

When we met, her designs had gained attention in a show in New York, not least her plans for a UFO-like "gentleman's club" in Hong Kong, and this led to her commission to design a restaurant interior in Sapporo, Japan, which she undertook with ice and fire themes. "What I find exciting is the degree of manipulation one can impose on any brief," she smiled, passing me another espresso. I dropped a jagged splatter onto one of her compositions of a cityscape. Unfazed, she said, "It's after midday – shall I open a bottle of wine?"

I still secretly hope my stain will one day become a building.