Preheat the oven to 350°F (175°C). Grease and flour a loaf pan.

In a mixing bowl, cream together the softened butter and granulated sugar until light and fluffy.

Add the eggs one at a time, mixing well after each addition.

In another bowl, whisk together the flour, baking powder, and salt.

Gradually add the dry ingredients to the butter mixture, alternating with the sour cream. Mix until just combined.

Stir in the key lime zest and juice.

Pour the batter into the prepared loaf pan and smooth the top.

Bake for 60 minutes or until a toothpick inserted into the center comes out clean.

Allow the cake to cool in the pan for 10 minutes, then transfer to a wire rack to cool completely.

In a small bowl, whisk together the powdered sugar and key lime juice until smooth.

Drizzle the glaze over the cooled pound cake.