In a glass, mix the yogurt, plant-based milk, and vinegar. Let sit for 10 minutes.

In a large bowl, combine the flours, salt, baking soda, guar gum, and sugar.

Melt the chocolate and butter together.

Grate the zucchini and cut it into pieces. Place in a blender bowl.

Add the yogurt-milk-vinegar mixture and flax seeds to the blender, then blend.

Add the melted chocolate and blend again.

Gradually add about 1/4 of the flour mixture and blend.

Pour the blender mixture along the edge of the flour bowl and gently fold in the flour until combined.

Taste: If it's not chocolatey enough, add 1 to 2 tablespoons cocoa powder and more sugar if needed.

Bake for 35 minutes at 350°F (180°C) in a preheated oven. If needed, bake longer (check with a knife; it may take time to rise).

Melt the 3.5 oz chocolate and fill any holes formed during baking. Sprinkle the cracks with flaky sea salt and chopped almonds.