Bake white cake in 4 round pans and let layers cool completely.

Thaw coconut for 2 days, then mix with lukewarm water and cream of coconut until evenly moist.

Prepare coconut buttercream icing with a slightly thin consistency.

Slice cake layers if needed to create at least 4 even layers.

Spread a thin layer of buttercream on each layer, then add coconut filling.

Continue layering cake, buttercream, and filling until fully stacked.

Frost the outside with a thin layer of buttercream.

Cover the cake with remaining coconut filling, pressing gently to stick.

Refrigerate for 2–3 days to set flavor and texture.