Preheat oven to 350 degrees F. Grease baking dish or line it with parchment paper.

In large mixing bowl, whisk together pumpkin puree, cane sugar, coconut milk, sweetened condensed milk, melted butter, vanilla extract and eggs until smooth.

Add sweet rice flour, baking powder and pumpkin pie spice.

Gradually fold dry ingredients into wet mixture, stirring until well incorporated and batter is smooth.

Pour batter into baking dish, spreading it evenly. Bake for 1 hour or until top is golden brown and toothpick inserted into center comes out clean.

Let cake cool completely before cutting it into squares.