Salted Breton butter, churned from cultured cream and shot through with crystals of coarse salt, is the ingredient that underwrites almost every dish in the region.
Where to eat it: 3 restaurants across 1 city.
The habit is a tax accident. The gabelle, the French salt tax, exempted Brittany from the fifteenth century onwards, so salt stayed cheap in the region long after it became a luxury elsewhere, and Breton dairies went on salting butter for preservation when the rest of France moved to sweet butter. Demi-sel carries between 0.5 and 3 percent salt; anything more is beurre salé. The best is churned slowly from cream ripened with lactic cultures overnight, then finished with fleur de sel from the Guérande pans so the crystals stay whole. In Rennes it goes on bread at the table, into the caramel and into the pan for every galette.
Common allergens: Dairy
Tip from the editors. Wash it until the water runs completely clear. Every trace of buttermilk left in the butter cuts its keeping time by days.
The Marché des Lices has run in Rennes since 1622 and now packs close to 300 stallholders onto Place des Lices every Saturday, France's second-largest market.
Tip: The galette-saucisse stands between the two halls fire up from sunrise; go before 11:00 to beat the queue that swallows the square.
The Halles Centrales put a daily covered market in the middle of Rennes, 28 fishmongers, cheesemongers, butchers and greengrocers under the Criée's 1922 roof.
Tip: This is the everyday market when it is not Saturday, and Sunday 09:00 to 13:00 is the only food shopping left in the city that day; BioCrêp inside griddles a €3.50 organic galette-saucisse.
Le Fournil des Halles bakes a three-generation kouign-amann recipe near the Halles Centrales in Rennes, alongside far breton and buckwheat galettes.
Tip: Their kouign-amann is sold in packaging that keeps it three weeks, the one Breton pastry that survives a suitcase.
Worth the queue: Kouign-amann, plain or apple
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