Thaw cherries, reserving about 2 tablespoons of juice.

Sprinkle unflavored gelatin over 1 cup of coconut milk in a bowl and let stand.

In a saucepan, combine sugar, vanilla extract, cinnamon, cardamom (if using), and the remaining 3 cups of coconut milk.

Bring to a simmer over medium-low heat, whisking constantly until sugar is dissolved.

Pour the hot coconut mixture over the gelatin mixture and stir until the gelatin is completely dissolved.

Stir in the reserved cherry juice.

Let the mixture stand for 20 minutes to cool slightly.

Lightly grease a 6-cup gelatin mold with vegetable cooking spray.

Place cherries in a single layer in the bottom of the mold.

Pour enough gelatin mixture over the cherries to cover them halfway.

Chill for 20-30 minutes, or until slightly set.

Let remaining gelatin mixture stand at room temperature to prevent premature setting.

Slowly pour enough of the remaining gelatin mixture into the mold just to cover the cherries.

Chill for another 20-30 minutes, or until slightly set.

Slowly pour the remaining gelatin mixture into the mold.

Chill for at least 6 hours, or until the mold is firm.

Gently run a small knife around the outer edge of the mold to break the seal.

Dip the bottom of the mold in warm water for about 10 seconds to loosen the mold.

Invert the mold onto a serving plate.