At the Mamiche bakeries in the 9th and 10th arrondissements of Paris, their famous pains au chocolat and croissants depend on an essential but increasingly scarce ingredient ¡ª butter.

The bakery¡¯s regular supplier can no longer provide a steady flow of French beurre de tourage, a type of flat butter used to make the pastries. Mamiche has gone searching elsewhere to ensure the steady flow of sweet treats from its ovens, but it¡¯s coming with a cost.

Butter prices in most of the world are lingering near record highs, with little end in sight to the surge. It¡¯s the result of a complex interplay of factors ¡ª challenges faced by dairy farmers from France to New Zealand, changes in Asian consumers¡¯ appetites that¡¯s spurring global demand, and commercial decisions by milk processors defending their bottom line.