Preheat your oven to 350°F (175°C) and grease a 9×13-inch baking pan.

In a bowl, whisk together flour, baking powder, and salt, and set aside.

In another bowl, cream the softened butter and sugar until light and fluffy (about 3 minutes).

Add eggs one at a time, mixing well after each addition. Stir in vanilla extract until smooth.

Gradually mix in the dry ingredients until just combined; gently fold in the cranberries.

Transfer batter to the prepared pan and smooth the top.

Sprinkle the cinnamon-sugar mixture over the top.

Bake for 35-40 minutes or until golden brown; check with a toothpick for doneness.

Cool for 10 minutes in the pan before transferring to a wire rack.