Dissolve the glucono delta-lactone by stirring the Glucono delta-lactone (GDL) into about 1/4 cup of warm Water until fully dissolved; set this coagulant solution aside.
Warm the Soy Milk in a heavy saucepan over medium heat, stirring occasionally to prevent a skin from forming, until it is steaming and just below a simmer (small bubbles at the edge) — do not boil.
Remove the pan from the heat and let the soy milk cool for a few minutes so the temperature drops slightly (it should still be very warm but not scalding).
Slowly and gently stir the dissolved coagulant into the warm soy milk, mixing evenly but without vigorous agitation; then immediately pour the mixture into individual serving bowls or a shallow serving dish.
Cover the bowls and leave undisturbed in a warm spot for 20–30 minutes (or until the soy milk sets into a soft, custard-like texture).
While the tofu sets, make the gula melaka syrup: put broken or chopped Gula Melaka (Malaysian palm sugar) and about 1/2 cup of Water in a small saucepan with a couple of bruised Pandan Leaves. Bring to a gentle simmer, stirring until the sugar dissolves and the mixture becomes glossy.
If you prefer a slightly thicker syrup, mix the Cornstarch with a tablespoon of cool water to make a smooth slurry, then whisk the slurry into the simmering palm sugar syrup and cook for another minute until the syrup lightly thickens. Remove the pandan leaves and cool slightly.
Spoon the warm syrup over the set tofu and serve immediately, or chill the tofu and serve the syrup warm or cold according to your preference.
