Preheat the Oven & Prepare the Cake:
Preheat your oven to 350°F (175°C). Grease and flour a 9×9-inch baking pan or line it with parchment paper.

Make the Cake Batter:
In a medium bowl, whisk together flour, sugar, baking powder, baking soda, and salt. In a separate bowl, beat the softened butter and egg until light and fluffy. Add the brewed coffee, buttermilk, and vanilla extract, then mix well. Gradually add the dry ingredients to the wet ingredients, stirring until smooth.

Bake the Cake:
Pour the cake batter into the prepared pan and bake for 25-30 minutes or until a toothpick inserted into the center comes out clean. Let the cake cool for 10 minutes in the pan, then transfer it to a wire rack to cool completely.

Prepare the Caramel Sauce:
In a saucepan, combine brown sugar, butter, and heavy cream. Stir constantly over medium heat until the mixture simmers. Let it simmer for 3-4 minutes until it thickens. Remove from heat, stir in vanilla extract and salt, and set aside.

Make the Coffee Drizzle:
In a small bowl, mix brewed coffee and powdered sugar until smooth.

Assemble the Cake:
Once the cake has cooled, poke holes all over the surface using a fork or skewer. Pour the caramel sauce evenly over the cake, allowing it to soak in. Drizzle the coffee mixture over the top for an extra coffee kick.

Serve:
Serve the cake warm or at room temperature. Top with whipped cream or vanilla ice cream for extra indulgence.