Heat the oven to 350° F. Rub bottom and sides of a 9" springform pan with a little olive oil then line with parchment paper.
Beat the egg yolks and sugar until sugar dissolves somewhat and thick, pale ribbons of batter form. Mix in the olive oil, lemon juice and zest, orange zest and orange blossom water. Gently crushed dried green cardamom pods with a rolling-pin and remove the black seeds inside. Discard the outer pod. Continue until you have one teaspoon of the cardamom seeds. Add to the batter.
In another bowl, beat the egg whites and salt until stiff peaks are formed.
Into a third bowl, sift the cake flour.
Add the flour to the egg yolk batter. Then gently fold in the beaten egg whites, taking care not to lose the volume of the egg whites.
Fold in half of the grapes.
Pour the batter into the prepared springform pan. Bake for about 20 minutes, then quickly pop open the oven and scatter the remaining grapes over top. Using your finger, gently press the grapes to partially submerge them into the cake. Leave some more exposed than others. Close the oven door and continue to bake for an additional 25 minutes or until a skewer poked in the middle of the cake comes out clean. The cake will be quite high initially and slowly lose some of that height as it cools.
Leave the cake in the springform pan and gently brush melted honey over top. Sprinkle coarse white sugar over top and finish with a dusting of regular sugar.
Allow the cake to cool in the springform pan, then gently remove and place on your serving plate.