The longer I stay in Thessaloniki, the more attuned I become to its rhythms. If it's breakfast time, you might go to Serraikon, in Modiano, or to Athina, over on Vasilisis Olgas Street, for bougatsa, a flat, flaky pastry filled with feta or sweet custard—or buy one of the sesame-covered bread rings called koulouria from a vendor on any street corner. At lunchtime, people descend on Diagonios, a psistaria (grill house), for gyros, which in this city means a plate piled with crisp-around-the-edges pork garnished with onion. In the late afternoon, you could stop at Hatzis, a patisserie that's been making the syrup-soaked pastries called siropiasta since Thessaloniki was an Ottoman city—extravagant things like revani, a semolina cake drenched in syrup, and kazan dipi, a buffalo milk pudding torched like a creme brulee. In the wee hours, you might find yourself under the fluorescent lights of Derlikatesen, alongside university students coming off a night in the bars and waiting hungrily for souvlaki, succulent chunks of grilled marinated pork wrapped in a pita along with thick-cut french fries and tsatsiki (yogurt and cucumber sauce) or yellow mustard. But the best insurance against a hangover, or so I'm told, can be had at Tsarouhas, a patsatzithiko (all-night tripe house) open since 1952, in the form of a bowl of the soothing, velvety tripe soup called patsas.