Preheat oven 350 degrees F (180 degrees C).
Butter or spray two 9 x 4 loaf pans. Line the bottom with parchment or aluminum paper.
In a large bowl beat Unsalted Butter (1 1/8 cup) and Sour Cream (8 ounce) until smooth, about 1 minute.
Add Lime (1) and mix. Add Granulated Sugar (3 cup) gradually and beat until light and fluffy, about 3 minutes more.
Add Egg (6), one at a time, incorporating well each one before adding the next. Add Vanilla Extract (1 teaspoon) and juice from the Lemon (1/2).
Sift Cake Flour (3 1/4 cup) with Baking Soda (1/4 teaspoon) and Salt (1/4 teaspoon) and add it to the butter mixture at low speed in 2 additions, beating only until mixed.
Pour into the pans and bake for 45 minutes or until golden and cracked on top and a tester comes out clean.
Let cool for 10 minutes then unmold. Let cool completely before glazing.
For the glaze, mix Powdered Confectioners Sugar (3/4 cup), Lime Juice (1 tablespoon), and Lemon Juice (1 tablespoon) until smooth. Pour slowly along the center of the cake, letting it slide to the sides. Serve and enjoy!