Preheat your oven to 160°C (320°F) for fan-forced or 180°C (356°F) for conventional. Grease a baking dish with olive oil.

Whip aquafaba in a bowl on high speed until stiff peaks form, about 5–7 minutes.

Blend raw shelled pistachios and sugar in a food processor until a fine powder is achieved.

In a large bowl, whisk together ground pistachios, flour, cornstarch, baking powder, baking soda, and salt.

Mix soy milk, apple cider vinegar, olive oil, and vanilla extract until well combined in a separate bowl.

Fold the wet ingredients into the dry mixture gently, then fold in the whipped aquafaba.

Pour the batter into the baking dish and bake for 35-45 minutes, until a skewer comes out clean.

Let the cake cool in the pan for 10-15 minutes. Poke holes in the top with a skewer.

Whisk pistachio butter, condensed coconut milk, evaporated coconut milk, and almond milk together. Pour over the cooled cake.

Cover and refrigerate for at least 4 hours or overnight.

Whip the chilled coconut cream until stiff peaks form and fold in some pistachio butter. Spread over the cake before serving.

Garnish with chopped pistachios and serve.