Preheat oven to 350 degrees F.
Zest three large lemons for about 2/3 cups lemon zest. Combine the sugar and lemon zest and smash together. Add the eggs and salt and whisk together until evenly blended and frothy.
Combine the flour and baking powder in a sifter. Sift in 1/3 of that mixture into the frothy egg mixture and add poppy seeds. Evenly whisk previous ingredients together then add in the rest of the flour in two more rotations, 1/3 of the mixture each time. Next, mix in the cream then fold in the butter.
Grease and flour a 9×5-inch loaf pan. Pour the batter into the pan. Bake at 350 degrees F for about 60 minutes – until the top is a light to medium brown and there’s a crack along the top, or a toothpick inserted in the center comes out clean.
Let the bread rest for 10 minutes before removing from pan then let cool top side up. Cut and enjoy!