Instructions:
Preheat your oven to 350°F (175°C) and prepare a 9-inch springform pan by greasing it or lining it with parchment paper.
In a large bowl, whisk together the flour, baking powder, and salt until well combined. Set aside.
In another bowl, beat the eggs, granulated sugar, olive oil, softened butter, orange zest, lemon zest, and vanilla until the mixture is light and fluffy.
Gradually add the eggs to the sugar mixture, incorporating them one at a time. Then, gently fold in the dry ingredients in stages until just combined.
If desired, coat the grapes with a bit of flour to prevent them from sinking, then carefully fold the grapes into the batter.
Pour the batter into the prepared springform pan and bake in the preheated oven for 20 minutes at 400°F (200°C). After 20 minutes, reduce the temperature to 350°F (175°C) and continue baking for an additional 35-40 minutes, or until a toothpick inserted in the center comes out clean.
Once baked, allow the cake to cool in the pan for 10 minutes before transferring it to a wire rack to cool completely.
Dust the cooled cake with powdered sugar before serving. It pairs wonderfully with whipped cream or a scoop of vanilla ice cream.
For the best results, consider experimenting with different grape varieties to discover your favorite flavor combinations. Remember to use whole grapes, especially the smaller ones, to maintain the cake's texture.
If you want to add a twist, try incorporating a hint of cinnamon for warmth, or consider substituting wine or buttermilk for a non-alcoholic version. Enjoy the process and the delightful aroma that fills your kitchen while baking this Italian Grape Cake!