Preheat oven to 350° F. Prepare a 9-inch loaf pan with nonstick cooking spray and parchment paper.
In a large mixing bowl or the bowl of a stand mixer fitted with a paddle attachment, add room temperature unsalted butter and granulated sugar. Cream the butter and sugar on medium speed for a few minutes until well combined.
Add room temperature eggs and continue to mix until smooth. Scrape the sides and bottom of the bowl.
Add lemon juice, lemon zest, and heavy cream. Continue to mix on medium speed until well combined.
Add all-purpose flour, baking powder, and salt. Mix on low speed until just combined. Do not overmix. Scrape the sides and bottom of the bowl with a spatula to ensure the ingredients are mixed.
Pour the batter into the loaf pan and spread evenly.
Bake for approximately 35-40 minutes until the loaf is baked through. You can test for doneness by inserting a toothpick in the center of the loaf cake. When removed, it should come out clean.
Allow the lemon loaf to cool in the pan for about 15 minutes. Remove the loaf from the pan and transfer to a wire rack to cool to room temperature.