Adjust the temperature of oven around 350°F (175°C). To make the removal easier, line the bottom of a 9 inch round cake pan with grease and flour or with parchment paper.
Mix the flour, baking soda, salt and baking powder in amedium bowl.
In a large bowl, now cream the softened butter and granulated sugar until it is fluffy and light in a large bowl.
Beat the eggs, one at a time, until each one is completely mixed in before adding the next one. Now, the key lime juice and key lime zest.
To the wet mixture add the dry ingredients, with buttermilk coming in first and the dry ingredients at last. Mix the mixture well.
Mix the vanilla extract.
After pouring the cake batter into the pan, evenly distribute it. Now, just bake it around 25-30 minutes until the toothpick at the center comes out clean.
Let’s cool the cake in the pan for around 10 minutes, then put it on the wire rack to cool completely.
While the cake is cooling, it’s time to prepare the key lime glaze by adding the key lime juice and powdered sugar in a bowl. You can add milk to it to make it thinner. Mix until it is smooth.
After the cake is cool completely, sprinkle the key lime glaze on the top of cake. You can garnish it with extra key lime zest for additional flavor.
Now cut the cake and enjoy it!