Preheat oven to 325°F.
Line pan with parchment paper.
Cream butter and sugar until light.
Add eggs one at a time.
Mix in vanilla extract gently.
Whisk flour, baking powder, and salt.
Add dry mix to wet mix slowly.
Pour in buttermilk, mix until combined.
Pour batter into prepared cake pan.
Bake for 45-50 minutes until golden.
Check with a toothpick for doneness.
Cool on rack for 15 minutes.
Remove from pan and cool fully.
Dust with powdered sugar before serving.
Drizzle caramel sauce if desired.