Preheat oven to 350 degrees. Grease a loaf pan and set aside.
Combine the flour, baking powder and salt in a medium sized mixing bowl using a whisk.
In a larger bowl, cream the butter and sugar together until fluffy. Beat in the eggs one at a time. Then mix in the vanilla, lemon extract, lemon zest, lemon juice, and heavy cream.
Mix about half of the flour mixture into the butter mixture. Stir to combine and mix in the other half. Pour the batter into the prepared loaf pan and bake 50-60 minutes, or until a toothpick comes out clean when inserted into the center.
Cool completely before adding the icing.
While the loaf is cooling combine the icing ingredients in a small mixing bowl and stir together until smooth.
Transfer the cooled loaf to a cutting board or plate and drizzle the icing over the top. Slice and serve.