Preheat the oven to 200°C and line the muffin pan with 12 muffin liners. Set aside.
To the unsweetened almond milk, add apple cider vinegar and stir. Set aside.
To the mixing bowl, add white cane sugar, brown sugar, and melted coconut oil. Mix with a whisk until it combines. Add vegan yogurt, vanilla extract or paste, and mix again. Then add the vegan buttermilk. Mix until combine.
To the wet mixture, sift all-purpose flour, cornstarch, baking soda, baking powder, and a pinch of sea salt. Mix with a whisk until just combined. Don't overmix the batter. Then add vegan chocolate chips or chopped chocolate bar and stir it in.
Evenly divide the batter into 12 muffin liners. Add some additional chocolate chips on the top and place the pan into the preheated oven.
Bake at 200°C for 5 min, then turn the oven to 180°C and bake for 17 min. The muffins are done if a toothpick inserted into the middle comes out clean. Otherwise, bake for 2-5 minutes longer.
Let the muffins cool in the pan for about 15-20 minutes, then place them on a cooling rack and let cool completely.