Preheat your oven to 170° C (340°F) conventional heat and line or grease a 26 cm springform pan with parchment paper.
Insert the butterfly whisk into the mixing bowl.
Separate the eggs, add the egg whites to the mixing bowl, and whip until stiff peaks form, 3 min / speed 3.5. Transfer to a separate bowl and remove the butterfly whisk.
Next, add the quark, sour cream, and egg yolks to the mixing bowl and mix for 1 min / speed 4.
Finally, add the melted butter, sugar, bourbon vanilla sugar, baking powder, vanilla pudding mix, and lemon juice, and mix for 2 min / speed 4.
Transfer the batter to a mixing bowl, add the whipped egg whites, and gently fold them in with a whisk.
Pour the cheesecake mixture into your prepared springform pan, smooth out the top, and bake for about 60 minutes in the lower third of your oven.
Once the baking time is up, turn off the oven, prop the door open slightly, and let the cheesecake rest inside for another 15 minutes.
Remove from the oven and let it cool completely before serving.
Top with fresh fruit and a drizzle of raspberry or strawberry sauce, if desired!
Notes
This cheesecake turns out ridiculously creamy and tastes absolutely phenomenal!