Preheat the oven to 170°C (338°F).
Trim and finely chop the mugwort.
Sift the isolated soy protein and set aside.
In a bowl, mix the eggs, erythritol, and oil together.
Add the isolated soy protein, baking powder, and mugwort, and mix well.
Pour the batter into a pound cake mold.
Bake at 170°C for 25 minutes.
Let cool and cut into bite-sized pieces.