Crush the ginger biscuits into fine crumbs—I like to use a food processor for a uniform texture, which helps the crust hold together better. Pour the melted and slightly cooled butter over the crumbs and mix until the mixture resembles wet sand. Press this mixture firmly and evenly into the bottom of a 9-inch springform pan, using the bottom of a measuring cup to compact it. Refrigerate the crust while you prepare the rhubarb and filling.

Preheat your oven to 200°C (400°F). Spread the rhubarb pieces on a baking tray and scatter the star anise among them. Pour the grapefruit juice over the rhubarb and sprinkle with sugar. Roast for 5-10 minutes until the rhubarb is just tender but still holds its shape—you want it softened but not falling apart. Remove from the oven, discard the star anise, and set aside the rhubarb with its poaching liquid to cool slightly.

In a large bowl, combine the cream cheese, sifted icing sugar, lemon zest, lemon juice, finely chopped ginger balls, and vanilla extract. Beat on medium speed until smooth and well combined—I like to scrape down the bowl halfway through to ensure no lumps remain. In a separate bowl, whip the cream to soft peaks, then gently fold it into the cheese mixture until just combined. This creates a lighter, more delicate texture than beating everything together.

Pour the cheesecake filling from Step 3 over the chilled crust from Step 1, spreading it evenly to the edges. Smooth the top with a spatula. Cover loosely with plastic wrap and refrigerate for at least 2-3 hours, or overnight if possible, until the filling is fully set and firm to the touch.

Remove the cheesecake from the refrigerator 10 minutes before serving to let it warm slightly—this makes it easier to release from the pan and gives better flavor. Release the springform pan sides and transfer the cheesecake to a serving plate. Top with the poached rhubarb from Step 2, drizzle generously with the reserved poaching syrup, scatter extra ginger biscuit crumbs over the top, and garnish with fresh mint sprigs for brightness and color.