Instructions
Prepare the flax egg: In a small bowl, mix ground flaxseed with water. Set aside to thicken for 5 minutes.

Whip the aquafaba: In a clean bowl, beat aquafaba and cream of tartar with a hand mixer until stiff peaks form. Add sweetener gradually while mixing.

Make the batter:

In a separate mixing bowl, whisk together the coconut milk, almond milk, vanilla, sweetener, and flax egg.

Slowly add in coconut flour, almond flour, tapioca starch (if using), salt, and turmeric (if using). Whisk until smooth.

Fold in the whipped aquafaba: Gently fold the whipped aquafaba into the batter in three parts. Don’t overmix—it’s fine if some lumps remain.

Bake:

Preheat oven to 160°C (320°F).

Pour the batter into a greased or lined square baking dish (around 20×20 cm).

Bake for 45–55 minutes, or until the top is golden and puffed up.

Cool and chill: Let it cool at room temperature, then refrigerate for at least 4 hours (or overnight) to allow the layers to set.

Serving
Slice carefully. You should get three layers:

A dense base

A custardy middle

A soft sponge top

Top with a dusting of powdered erythritol or serve with fresh berries if desired.