Preheat the oven to 350°F (180°C). Grease a 9x5 inch (23x13 cm) loaf pan with butter and line with parchment paper, leaving a few inches of overhang.

In the bowl of a stand mixer, rub the sugar and lemon zest together with your hands until fragrant and pale yellow. This helps to release the natural oils.

Fit the stand mixer with a paddle attachment and add the butter to the bowl of lemon sugar. Beat on medium speed for 2-3 minutes until pale and fluffy, scraping down the bowl halfway though with a silicone spatula.

Add the eggs one at a time, mixing well in between each addition. Scrape down the bowl again and add the ricotta. Continue mixing on medium speed for 1 minute.

Mix in the lemon juice and vanilla extract (it will look curdled at this point, but it's ok). Then with the mixer on low speed, gradually add the flour and mix until there's a few streaks left.

Transfer the batter to the prepared loaf pan and smooth out the top. Bake for 1 hour 5 minutes to 1 hour 10 minutes or until a cake tester inserted into the center comes out clean or ideally with a few soft crumbs. During the last 15 minutes of baking, loosely place a tent of foil over the loaf to prevent over browning. 

For the glaze, add the powdered sugar, lemon juice, and lemon extract (optional) to a small bowl. Whisk until smooth and drizzly then pour over the fully cooled cake. Decorate with fresh blueberries and lemon zest if desired. Enjoy!