Whisk together the eggs and the sugar on full speed until light and fluffy.
Add the powdered almonds and the almond extract. Then add the butter and mix until you get homogeneous batter.
Separate the batter in two halves. Add the chocolate spread and the cocoa powder to one.
Fill the cake mold with the help of two ladles (or normal tablespoons, depending on the pattern you want to get) altering the white and chocolate batter.
When both batters are gone, take a fork, put it into the dough at one end of the mold and push it to the other end. Now you got the final swirl.