First of all, Pre-heat your oven to 350 F (180 C). Oil and flour an 8 1/2-x-4 1/2-inch loaf pan. Now Line the bottom and sides with parchment paper.
Add the sugar to a large bowl. Finely zest the lemons and stir them in. Mix in the eggs. Next, add the cream, oil, and vanilla.
After this, Mix the flour, baking powder, and salt in a bowl. Continue to whisk the batter until it is smooth. After this, Add the blueberries to the batter and stir. Bake for 60-70 minutes or until a toothpick inserted into the middle of the cake comes out clean.
After this, Let the cake cool in the tin for 20 minutes before turning it out onto a rack to cool.
Now Make the icing by whisking the lemon juice and icing sugar together until it is smooth and creamy.
Let the mixture cool on the loaf. You can slice the loaf immediately, or let it cool for at least an hour to allow the glaze to set up so that you can slice more efficiently. The loaf can be kept covered on the counter for up 4 days.