01 -
Place the almond flour, all-purpose flour, cold butter, and sugar in the bowl of a food processor. Pulse until the mixture forms fine crumbs. Transfer to the refrigerator to keep cold. Grease and line the base and sides of a 23 cm springform cake pan.
02 -
Preheat oven to 165°C.
03 -
In a medium bowl, whisk together all-purpose flour, baking powder, baking soda, and salt.
04 -
In a stand mixer bowl fitted with the paddle attachment or using an electric hand whisk, beat butter and sugar on medium-high speed until light and fluffy, about 3 minutes.
05 -
Scrape down the sides of the bowl, add the eggs and vanilla, and mix until just combined.
06 -
Add the flour mixture and sour cream to the butter mixture in three additions, alternating and beginning and ending with the flour. Mix until just combined. Pour the batter into the prepared cake pan and refrigerate for 20 minutes to firm up.
07 -
Arrange sliced nectarines and blueberries evenly over the batter. Sprinkle approximately 60 g (about 1/2 cup) of the cold streusel topping over the fruit.
08 -
Bake for 35–40 minutes, or until the cake is golden, the blueberries have burst, and the surface springs back when pressed lightly. A toothpick inserted in the center should come out clean.
09 -
Allow the cake to cool in the pan for 15 minutes, then transfer to a wire rack to cool completely before slicing.