Mix the flours, baking powder, milk, salt, 1 teaspoon butter, egg, and sweetener in a bowl. Mix until smooth. Let it rest for at least half an hour in the refrigerator.
If making chocolate ganache: In a bain-marie or water bath, melt the chocolate with 1/4 cup water. When the chocolate has completely melted, add the liqueur. Let the alcohol evaporate, about 3 minutes, before turning off the fire. Set aside.
Warm-up a medium skillet. Rub a bit of coconut oil or butter so that the pancakes won't stick. Ladle some of the pancake mixture on the skillet then immediately drop some blueberries on the pancake. When the pancake starts to move easily on the skillet, cook the other side. Repeat until mixture is finished.
To make smaller round shapes, use a cookie cutter with a 3-inch diameter. One pancake can yield 4 smaller pancakes.
Pile 3 small pancakes alternating with the chocolate ganache.
Pour the chocolate ganache on top then garnish with blueberries (and strawberries if you have) and fresh mint leaves, if using. Sprinkle with icing sugar, if using.