Preheat oven to 350 F. Grease and flour a 9x5 loaf pan. Tap out the excess flour. In a large bowl, whisk together eggs, salt and sugar for about a minute just until the mixture is bubbly. Add the grated zest and whisk together.

Combine flour and baking powder in another bowl. Sift about 1/3 of the flour mixture into the egg mixture. Whisk by hand using a wire whisk to combine. Sift the flour mixture in two more additions. Whisk just until everything is combined. No need to overdo it.

Whisk in the heavy cream. Switch to a rubber spatula and fold the melted butter. Pour the batter into the loaf pan. Bake in the center rack of the oven for 50-60 minutes. A toothpick inserted at the center of the cake should come out clean. The top should crown and crack. Transfer to a wire rack and let the cake cool slightly in the pan. Remove from the pan and let cool completely.