Line the base of a 20–22 cm / 8–9 inch springform tin with baking paper.
Grease the sides of the springform tin thoroughly.
Place the pecans in a food processor.
Process the pecans until they form a fine flour-like texture. Do not over-process, as the pecans may turn into nut butter.
Add the melted butter, almond flour, granulated sweetener, ground ginger, ground cinnamon, ground nutmeg, and cardamom seeds to the ground pecans.
Blend until the crust mixture is fully combined and holds together when pressed.
Transfer the crust mixture to the prepared springform tin.
Press the mixture firmly and evenly into the base of the tin using clean fingers or the back of a spoon.
Place the prepared crust in the refrigerator while preparing the filling.
Preheat the oven to 160°C / 320°F electric.
Place the eggs in a large mixing bowl.
Beat the eggs for approximately 2 minutes, or until creamy and fluffy.
Add the full-fat cream cheese, heavy cream, powdered sweetener, brandy, orange extract, and finely grated orange zest.
Mix until just combined and smooth. Avoid overmixing.
Taste the filling and add additional sweetener if desired.
Remove the chilled crust from the refrigerator.
Pour the cheesecake filling evenly over the crust.
Smooth the top gently with a spatula if necessary.
Place an oven-proof bowl filled approximately 2 fingers high with just-boiled water in the oven beneath the cheesecake.
Place the cheesecake in the oven.
Bake for 1 hour 15 minutes, or until the cheesecake is just set and lightly golden on top.
Remove the cheesecake from the oven.
Allow the cheesecake to cool completely in the springform tin.
Once cooled, carefully remove the cheesecake from the springform tin.
Refrigerate until ready to serve.
Before serving, decorate with dried or fresh orange slices and additional orange zest.
Slice and serve chilled.