Dough: 1 cup all-purpose flour ¼ teaspoon kosher salt ⅓ cup cold water 1 stick high-quality unsalted butter, fully softened, divided Sugar Syrup: ¾ cup white sugar ¼ cup water 1 tablespoon water 1 cinnamon stick (Optional) 1 lemon, zested in large strips (Optional) Custard Base: ⅓ cup all-purpose flour ¼ teaspoon kosher salt 1 ½ cups milk 6 large egg yolks 1 teaspoon vanilla extract (Optional) Combine flour, salt, and cold water in a bowl. Mix with a wooden spoon…