Combine the lemon curd and ricotta in a food processor, and process until smooth. (The food processor is optional, but will make the cream smoother with that ricotta graininess)
Whip the cream until stiff - the beaters should be leaving tracks in the cream. Combine with the ricotta lemon mixture.
In a 10x14 baking dish, dollop in some of the cream. Arrange 8 graham grackers in a layer. Top with more cream, and blueberries.
Add two more layers of graham crackers, cream, and blueberries. Finish with a top layer of blueberries. Sprinkle lemon zest over the top.
Allow to soften in the refrigerator at least 4 hours.
Recipe by The Domestic Front at https://www.thedomesticfront.com/lemon-blueberry-icebox-cake/