Preheat oven to 170 degrees Celsius, 338 Fahrenheit
Place the oven rack in the middle level.
Grease and flour a 22cm x 10cm (8.6" x 4") baking mold.
Vanilla batter: sift flour into a medium bowl, add baking powder and salt, and mix well.
Add oil, sugar, almond butter, milk, and vanilla extract and mix well until combined.
Chocolate batter: In another bowl, sift flour and cocoa powder, add baking powder and salt, and mix well.
Add oil, sugar, almond butter, milk, rum, and vanilla extract and mix well until combined.
Alternately transfer the batters to the mold: start with the vanilla layer in about half a cup, cover it with half a cup of the chocolate batter, repeat, and finish with the chocolate batter. (You will get four layers of vanilla and four layers of chocolate)
Draw the number eight several times in the batter using a wooden skewer or spoon handle. Don't insert the skewer deep; only the top two layers.
Bake for 60-70 minutes until a wooden skewer inserted into the center of the cake comes out clean.
Place the cake on a wire rack and cool it completely for several hours before removing it from the mold and slicing it. You can sprinkle a little powdered sugar on the cake.
