Preheat oven to 325°F (160°C). Line a non-stick loaf pan with parchment paper and lightly spray with cooking spray.

In a stand mixer, whip the aquafaba and brown sugar on high speed until the mixture becomes glossy and thick enough to hold soft peaks.

Melt the coconut oil and chopped chocolate together using a double boiler over medium heat. Stir until smooth, then let it cool slightly.

In a separate bowl, sift the flour, cocoa powder, sea salt, and baking soda.

Gently fold the cooled chocolate mixture into the whipped aquafaba. Add the dry ingredients and mix until just combined into a thick batter.

Pour the batter into the prepared pan and bake for 20 minutes, or until a toothpick inserted in the center comes out clean. Cool completely before cutting into chunks.

For the coconut whip, turn the chilled can upside down and open the bottom. Scoop out the firm cream, leaving the liquid behind.

Add the cream of tartar and sugar to the cream. Whip until fluffy, being careful not to overmix.

To assemble the sundae, place 3 scoops of chocolate frozen dessert into a bowl. Add brownie chunks, a spoonful of coconut whip, chocolate shavings, and chopped cherries. Serve immediately.