Line the base of an 8 inch (20 cm) round springform pan with baking paper.

In a large bowl, stir together the almond flour, coconut flour, and ground flaxseed until well combined.

Add 25 g powdered xylitol and mix again, then pour in the melted butter and stir until the mixture is evenly moistened and holds together when pressed.

Transfer the crust mixture to the prepared pan and press it firmly into an even layer over the base using the back of a spoon or the bottom of a glass.

Chill the crust in the refrigerator for at least 20 minutes while you prepare the filling.

In a large mixing bowl, beat the mascarpone and Greek yogurt together with a hand mixer until smooth and creamy.

Add 100 g powdered xylitol and the vanilla bean paste to the bowl and beat again until fully combined and silky.

In a separate bowl, whip the double cream to soft peaks using a hand mixer; it should hold its shape but look smooth, not grainy.

Gently fold the whipped cream into the mascarpone mixture in 2 to 3 additions, using a spatula and turning the bowl to keep as much air in the filling as possible.

Spoon the cheesecake filling over the chilled crust and spread it into an even layer, smoothing the top with a spatula.

Tap the pan lightly on the counter a few times to help settle the filling and release any large air bubbles.

Cover the pan and refrigerate for at least 6 hours, preferably overnight, until the cheesecake is firm enough to slice.

To serve, run a thin knife around the edge of the cheesecake, release the springform ring, slide off the baking paper, and transfer the cheesecake to a serving plate.

Slice into 12 portions with a sharp knife, wiping the blade between cuts for neat slices.