Sift tapioca starch and plain flour into mixing bowl. Weigh and take note of weight. Tuck pandan leaves in mixture. Bake at 160°C for 1 hour. Discard pandan leaves.

Re-weigh bowl and contents. If not lighter by 45 g or more, continue baking. When target weight is reached, turn off oven. Leave bowl in oven till almost cool. Re-sift starch and flour (in a plastic bag unless you enjoy dusting your kitchen). You should have about 335 g starch mixture. Leave till completely cool.

Whisk coconut cream, sugar, salt, egg and yolk till smooth. Cook over low heat, whisking, till sugar just melts. Turn off heat. Add butter. Whisk till incorporated. Leave till cool. You should have about 360 g coconut syrup.

Set aside 20 g baked starch for dusting. To remaining 315 g, add 315 g coconut syrup. Mix till well combined. Knead thoroughly till smooth and even, drizzling with remaining syrup as necessary, about 2 tbsp, so that dough just comes together. Cover and set aside 10 minutes.

Preheat oven to 160°C. Line baking tray with parchment paper. Lightly dust parchment paper with baked starch.

Lightly dust worktop and rolling pin with baked starch. Working with golf ball-sized  amount each time, roll dough 3 mm thick, dusting as necessary to prevent sticking. Cut dough with dusted cookie cutter measuring about 3 x 2 cm. Place cookies on baking tray spaced 1 cm apart.

Bake cookies till bottom is slightly brown and top has hint of colour around edges, about 15 minutes. Remove cookies to wire rack or plate to cool down. Serve immediately or store airtight.