☆Preparation
Preheat the oven to 190℃/ 374 F.
Mix the cake flour and baking powder.
Line a baking sheet with parchment paper or a silicone mat.

Mix the butter and peanut butter until smooth. Sift in the cane sugar and mix until smooth and continue mixing for another minute. Add the beaten egg and mix until smooth.

Dissolve the baking soda in 1/2 teaspoon of water. Add to the batter and mix well. Sift in the cake flour and baking powder, and fold gently.
When the dough starts to come together (it's okay if it's still powdery), add the oats and peanuts and mix by cutting the dough.

Fold until the oats and nuts are well distributed and you don't see any flour left.
Roll into 35g balls and make 12 balls. Lightly press each ball to flatten. Arrange them on a baking sheet, leaving 2-3cm of space between each ball.

Lower the oven temperature to 170℃ / 338 F and bake for 22 minutes.
Remove from the oven and let cool for 5 minutes. Transfer to a cooling rack and let cool completely.
★Store them in an airtight container at room temperature. Best eaten within 3-4 days.