Preheat the oven to 350°F and lightly grease a 12-oz oven-safe ramekin or dish.
In the ramekin, whisk together the yogurt, egg, egg white, maple syrup, cocoa powder, flaxseed, and salt until fully combined.
Bake for 35–40 minutes, until the center is set.
Remove from the oven and allow to cool on a wire rack for 1 hour, then transfer to the refrigerator to chill completely.
