SPICED SNACKING CAKE

Steps:

• Preheat oven to 350°F. Brush a 9-by-13-inch baking pan with oil. Line with parchment, leaving a 2-inch overhang on two sides; brush parchment. In a large bowl, whisk together flour, granulated sugar, baking powder, salt, cinnamon, and cardamom.
• In a medium bowl, whisk together egg and yolk, sour cream, oil, vanilla, and 3 tablespoons milk until combined. Add egg mixture to flour mixture; stir until smooth (batter will be thick). Transfer to prepared pan, smoothing top with an offset spatula.
• Bake until lightly golden and top of cake springs back when lightly pressed, 35 to 40 minutes. Transfer pan to a wire rack; let cool 30 minutes. Using overhangs, transfer cake from pan to rack; let cool completely.
• In a small bowl, whisk together confectioners' sugar, remaining 1 1/2 tablespoons milk, vanilla seeds, 1 1/2 teaspoons lemon zest (or up to 1 tablespoon, for a zesty bite), and 1 tablespoon lemon juice until smooth and pourable. (If glaze is too thick, add up to remaining 2 tablespoons lemon juice.)
• Pour over top of cake, spreading to edges with offset spatula. Allow to set before slicing, about 30 minutes. Cake can be refrigerated, wrapped in plastic, up to 3 days; return to room temperature before serving.