Preheat your oven to 350°F (175°C). Grease and flour a 9x13 inch baking pan.
In a mixing bowl, whisk together the flour, baking powder, baking soda, and salt. Set aside.
In a separate bowl, cream the softened butter and granulated sugar together until light and fluffy, about 3-4 minutes.
Add the eggs one at a time, beating well after each addition. Mix in the vanilla extract.
Gradually add the dry ingredients to the butter mixture, alternating with the sour cream. Start and finish with the flour mixture, mixing just until combined.
Gently fold in the cranberries using a rubber spatula.
Pour the batter into the prepared baking pan and spread it evenly.
Bake in the preheated oven for 45-50 minutes, or until a toothpick inserted into the center comes out clean.
Allow the cake to cool in the pan for about 10 minutes, then transfer it to a wire rack to cool completely before serving.
For a festive touch, consider dusting the cake with powdered sugar or serving it with whipped cream on top.