Preheat your oven to 375°F (190°C). Line the jelly roll pan with parchment paper, allowing some overhang on the sides for easy removal later.
In a large mixing bowl, using an electric mixer, beat the eggs and granulated sugar together on high speed for about 5 minutes until thick and pale in color. Add in the vanilla extract, lemon zest, and lemon juice, mixing until combined.
In a separate bowl, sift together the flour, baking powder, and salt. Gradually fold this dry mixture into the egg mixture using a spatula until just combined.
Gently fold in the fresh blueberries, being careful not to crush them.
Pour the batter into the prepared jelly roll pan and spread evenly. Bake for 12-15 minutes, or until the cake springs back when lightly touched.
Remove the cake from the oven and immediately flip it onto a clean kitchen towel dusted with powdered sugar. Peel off the parchment paper.
Roll the cake up gently with the towel, starting from one of the short ends. Let it cool completely in this shape, about 30 minutes.
While the cake cools, whip the heavy cream with the powdered sugar and teaspoon of lemon juice until soft peaks form.
Once the cake has cooled, carefully unroll it. Spread the whipped cream over the surface, then re-roll the cake without the towel, placing seam side down on a serving platter.
Decorate the top with additional blueberries and lemon zest if desired. Slice and serve chilled.