Prep the pan. Heat oven to 350°F (175°C). Butter a 9-inch round cake pan with at least 2-inch sides or use a 9-inch springform lined with foil to prevent leaks.

Make the cranberry topping. Melt 1/2 cup butter. Pour it into the pan, then sprinkle 3/4 cup brown sugar evenly over the butter. Scatter cranberries over the sugar in an even layer. Zest the orange over the berries for extra aroma.

Mix the dry ingredients. In a bowl, whisk flour, baking powder, baking soda, and salt. Set aside.

Whisk the wet ingredients. In another bowl, whisk 1/2 cup melted butter with granulated sugar until glossy. Whisk in eggs one at a time. Add vanilla, almond extract (if using), orange zest (about 1 tablespoon), and orange juice (1/3 cup). Stir in buttermilk. If you want extra moisture, add 1 tablespoon neutral oil.

Combine batter. Add dry ingredients to wet and stir gently until just combined. The batter should be smooth but not overmixed.

Assemble. Pour batter over the cranberries and smooth the top. The pan will be fairly full; that’s okay.

Bake. Bake 40–50 minutes, until the top is golden and a toothpick in the center comes out clean. If the top browns too fast, tent loosely with foil for the last 10 minutes.

Cool and invert. Let the cake rest 10–15 minutes on a wire rack. Run a knife around the edges. Place a serving plate over the pan and flip in one confident motion. Tap the bottom to release, then lift off the pan. Spoon any caramelized juices back on top.

Finish. Cool at least 20 minutes before slicing. Dust with powdered sugar if you like. Serve warm or at room temperature, plain or with whipped cream or vanilla ice cream.