"It's a cake from grandma's house with the ingredients of the farm: milk, flour, eggs. It's passed down in families," he said.
Up until the 1980s, Moulin de Bassilour made its fruit-filled version of the cake with apricot jam. Now, Lhuillier uses a local black cherry variety, which is another traditional flavour. His homemade pastry cream still remains the best seller.
"Many bakers flavour their pastry cream with almond, but on a farm we would never start to add an ingredient that costs a lot of money," he said. "Our flavouring is a bit of rum because in Basque country there's always a bit of rum on hand for cooling down the coffee."
Lhuillier says his commitment to the simplicity of the recipe is what keeps the bakery going year after year, and he feels proud to continue the tradition of his region.
"We haven't changed the recipe for more than 60 years but each generation that passes likes it, he said. "It's a Gâteau Basque that pleases the palettes of people who come from everywhere."
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