• Preheat the oven to 325°F (165°C). Grease and flour a 10-inch bundt pan.
• In a large bowl, cream together the softened butter and sugar and mix until light and fluffy. Add in the eggs and mix. Add in the sour cream and mix.
• In a separate bowl, whisk together the flour, baking powder, baking soda, and salt.
• Add the dry ingredients and mix until combined.
• Stir in the key lime juice, key lime zest, and vanilla extract, and mix well.
• Pour the batter into the prepared bundt pan and bake for 60-70 minutes, or until a toothpick inserted into the center of the cake comes out clean.
• Remove from the oven allow to cool in the pan for 15 minutes, and then turn over and out onto a rack and cool completely before frosting.

Make the frosting:

• In a medium bowl, beat the softened cream cheese and butter until smooth. You can use a stand mixer or a hand mixer.
• Gradually add the powdered sugar, key lime juice, vanilla, and zest of one lime, and continue to mix until the icing is smooth.
• Place the cooled cake on a serving platter and drizzle the icing over the top of the cake.
• Sprinkle with zested lime.
• Serve and enjoy!