• Preheat the oven to at 350°F. Butter and flour a 10" tube pan or Bundt pan. Combine the eggs, yolks, vanilla, sour cream and lime zest in a small bowl. Whisk to combine and set aside.
• Sift together the flour, salt and baking powder in a mixing bowl. Add the sugar to the flour and mix at low speed for 30 seconds. With the mixer running on low, add the butter a tablespoon at a time to the flour. Mix until combined. Add the lime juice and increase the speed to medium high. Mix for a full 2-3 minutes. The batter will lighten in color and texture. If you're using a hand mixer add another minute or two to the mixing time.
• Scrape the bowl and beater thoroughly. On low speed, add the egg mixture in 3 increments, scraping the bowl after each addition. Mix just until the eggs are incorporated.
• Pour 2/3 of the batter into the prepared pan and smooth to an even layer. Drizzle the lime curd over the center of the batter, trying not let it touch the sides or middle of the pan. Dollop the remaining batter over the curd and spread to cover. A little curd may show through on top, that's ok.
• Bake until the cake springs back when lightly pressed and a toothpick inserted in the middle comes out clean (about 40 minutes). A crack will probably form on the top of the cake.

Finish the Cake

• In a small bowl, combine the confectioner's sugar with the lime juice and zest. If it’s very thick add just a few drops of water or lime juice at a time until the glaze is the texture of pancake batter. Whisk until smooth.
• Cool the cake in the pan for 20 minutes, then turn it out onto cooling rack set over a clean sheet pan. Allow the cake to cool until it's slightly warm.
• Drizzle the lime glaze over the top of the cake. Allow the glaze to drip down the middle and sides of the cake.
• The glaze will set as the cake finishes cooling. Transfer to a serving plate.