Preheat your oven to 350 degrees F (175 degrees C). While that's heating, grease and flour a 9x5 inch loaf pan.
In a medium bowl, whisk together the cake flour, baking powder, and salt. Set aside.
Add the granulated sugar and Meyer lemon zest into a food processor. Process until combined, about five 1-second pulses.
Add the eggs, Meyer lemon juice, and vanilla extract. Process until combined, about 5 seconds.
With the machine running, slowly drizzle in the melted butter through the feed tube.
Transfer the mixture to a large mixing bowl. Sift the flour mixture over the wet ingredients in three additions, whisking gently after each addition until just combined.
Pour the batter into your prepared pan. Bake for 15 minutes. Reduce the oven temperature to 325 degrees F (163 degrees C) and continue baking for an additional 35 minutes.
Cool the cake in the pan on a wire rack for about 10 minutes.
In a small saucepan, combine the remaining granulated sugar and Meyer lemon juice. Bring to a boil over medium heat, stirring occasionally to dissolve the sugar.
Once the cake is slightly cooled, carefully remove it from the pan and place it on a wire rack. Using a toothpick, poke holes all over the top and sides of the cake.
Brush the warm glaze generously over the cake. Let it cool completely to room temperature.
