Preheat oven to 350°F (180°C) and position the rack in the lower third of the oven. Butter the sides and bottom of a 9-inch springform or cake pan. Line the bottom of the pan with parchment paper and butter the paper. If using a springform pan wrap it tightly with foil.
Put 4 Tbsp butter into the pan, transfer the pan to the oven and take it out when the butter is melted about 5 minutes.
Add the brown sugar and cinnamon to the pan, stir well until combined, then spread the mixture evenly over the bottom of the pan. Distribute the cranberries evenly on top. Set aside.
In the bowl of a stand mixer fitted with the paddle attachment cream the granulated sugar and remaining butter together at medium-high speed until pale and fluffy, about 4 minutes.
Then add the eggs. Mix for 30 seconds on high speed until combined.
Add sour cream, vanilla extract, salt, and lemon zest. Beat on medium speed until combined.
Sift cake flour, baking powder, and baking soda into the batter and mix on low speed until just combined and no lumps remain. The batter will be thick.
Spread the batter evenly over the cranberry mixture.
Bake in the lower third of the oven for about 50-55 minutes, until a skewer comes out clean with only a few moist crumbs attached.
Let the cake cool in the pan on a wire rack for 10 minutes. Then remove the ring of the springform or run a knife along the sides of the pan if using a normal pan. Invert the cake onto a serving plate and remove the bottom/pan.
Let cool for at least 15 minutes before serving.
Make sure to watch the video above the recipe card before you make the cake! I show you every step so you get the best results.