Preheat oven to 350F and line a 10×15 baking sheet with parchment paper.

To a large bowl, mix cassava flour, coconut flour, cacao powder, baking powder, sea salt and coconut sugar. Then make a well in the center of the dry ingredients.

In a separate bowl, combine avocado oil, maple syrup, coconut yogurt and vanilla extract. Then add wet ingredient mixture to the center of the dry ingredients.

Stir to combine the wet and dry ingredients into a soft dough.

Scoop dough out onto the center of the parchment lined baking sheet. Use your fingers to spread and smooth the dough out into an even layer. Then place another sheet of parchment paper on top and press or roll out the dough into a rectangle between ¼ and ½ inch thick about 12×9 inches.* Remove top sheet of parchment paper.

Bake in the middle rack of the oven for 16 minutes.

Remove from oven and transfer the pan to a wire cooling rack to cool completely.

Using the parchment paper, transfer the cake to a cutting board and cut it in half crosswise.

Carefully wrap each piece in plastic wrap and freeze for 1 hour, taking care not to crack the fragile cake while handling.**

15-20 minutes before you are ready to assemble, remove ice cream from the freezer and allow to soften a bit.*** Remove one half of the cake from the freezer and scoop ice cream evenly on top. Use an offset spatula to spread ice cream in an even layer to the edges.

Remove remaining piece of cake from the freezer and carefully place on top to make a sandwich. Re-wrap in plastic wrap and return to freezer for 8 hours or overnight.

Once fully frozen, remove from freezer, remove plastic wrap and trim edges to create a clean rectangle. Then, cut the large sandwich cake into squares or rectangles of desired size. Wrap individually in plastic wrap and keep frozen until ready to serve.