• Preheat oven to 350°F (175°C). Spray a 9×13-inch baking dish with baking spray.
• In a large bowl, whisk together the flour, baking powder, and kosher salt. Set aside.
• In the bowl of a stand mixer fitted with a paddle attachment, cream the butter and sugar on medium speed until light and fluffy, about 2–3 minutes.
• Add the eggs, one at a time, beating briefly after each addition. Then add the milk, vegetable oil, and vanilla extract, mixing on low speed until just combined.
• Gradually add the dry ingredients to the wet mixture, mixing on low until just incorporated. Be careful not to overmix.
• Remove bowl from mixer. Fold in cranberries.
• Pour the batter into the prepared pan, spreading it evenly. Set aside while you prepare the crumble.

Crumble

• In a medium bowl, combine the brown sugar, flour, and cinnamon.
• Add the cold butter pieces. Using a food processor, fork, or your hands, work the butter into the dry ingredients until it resembles coarse crumbs with pea-sized bits of butter.
• Sprinkle the crumble evenly over the cake batter.
• Bake for 50-55 minutes, or until a toothpick inserted into the center comes out mostly clean.
• Remove the cake from the oven and let it cool slightly.

Glaze

• In a small bowl, whisk together the confectioners' sugar and 2 tablespoons milk until smooth. Add a few more drops of milk if needed to reach a drizzling consistency.
• Drizzle the glaze over the warm cake. Slice and serve.