Preheat your oven to 350°F (175°C) and prepare a 9-inch springform pan by greasing it lightly.

In a large mixing bowl, cream together the softened unsalted butter and 1/4 cup granulated sugar until fluffy. Add the egg and vanilla extract, mixing until well incorporated.

In another bowl, whisk together the flour, baking powder, and salt. Gradually add to the butter mixture, mixing until a dough forms.

Press the cookie dough evenly into the bottom of the springform pan. Bake for 10-12 minutes or until golden. Cool slightly.

Beat the softened cream cheese until smooth, then add the sugar and vanilla extract, blending until fluffy.

Add eggs one at a time, mixing well after each addition. Stir in sour cream and flour until fully combined.

Pour cheesecake filling over the cooled crust. Smooth out the top and tap the pan to release air bubbles.

Bake at 325°F (163°C) for 40-50 minutes, or until the center is slightly jiggly but set at the edges.

Cool at room temperature for 30 minutes and refrigerate for at least 3-4 hours or overnight.

Remove from the springform pan and garnish with whipped cream, sugar sprinkles, and fresh berries before serving.