Preheat oven to 350 degrees. Coat the bottom and sides of a 9" springform pan with cooking spray, then dust pan with about 2 tablespoons semolina flour, tapping out the excess.
In a food processor, combine 1/2 cup sugar and the lemon zest. Process until moist about 15 seconds. Add the ricotta and cream cheese and process until smooth, about 30 seconds, scraping down the sides as needed. Add the semolina flour, egg yolks, Marsala wine, lemon juice, and salt. Process again until combined about 15 seconds. Transfer to a large mixing bowl.
In a stand mixer, whisk the egg whites on medium high until light and foamy. Slowly add the remaining 1/4 cup of sugar and continue to whip until they form firm peaks about 2-3 minutes.
Add half of the egg whites to the cheese mixture, stirring until combined. Lightly fold in the remaining egg whites until just incorporated. Transfer batter to prepared pan and spread into an even layer. Tap on the counter to release any air bubbles.
Bake for 45-55 minutes, until the top is lightly browned and the cake is just set, but still jiggles when shaken. (It is okay for an Italian cheesecake to crack on top, as this is part of its settling process.) Cool completely in the pan on a wire rack, about 1 hour. Cover and refrigerate for another 2 hours before removing from pan. Top with blueberry sauce. Serves 8-10.
To prepare Blueberry Sauce: In small saucepan, bring 1 cup blueberries, sugar, water, lemon juice, and lemon zest to a boil over medium-high heat. Reduce heat to low and simmer for 8-10 minutes, stirring occasionally until mixture thickens. Remove from heat and stir in remaining blueberries. Cool completely. Cover and chill until ready to serve over cheesecake.