Line two baking trays with baking paper. Separate the eggs. Beat the egg whites and 1 pinch of salt until stiff with the whisk of the hand mixer, adding 75 g of sugar. Beat the egg yolks separately under the egg whites.
Sift the flour, baking powder and spices on top and fold in.
Pour the sponge mixture into a piping bag with a small perforated nozzle (approx. 1 cm Ø). Spray approx. 36 bone-shaped strips (each approx. 8 cm long) onto the baking trays at a sufficient distance. Sprinkle with approx. 3 tbsp. sugar.
Bake one after the other in a preheated oven (electric oven: 175 °C/circulating air: 150 °C/gas: level 2) for about 12 minutes. Let them cool down.
Heat the cream in a small pot (do not boil!), remove from the heat. Finely chop the couverture and melt it in the cream while stirring. Pour into a bowl and chill for about 20 minutes until the cream is thick.
Simmer the jam in a small pot for about 2 minutes, then let it cool down for about 10 minutes.
Spread the chocolate cream with a teaspoon on the flat side of approx. 9 biscuits (use any cream left over otherwise). Spread the jam on approx. 9 more biscuits. Place the remaining sponge cakes on the coated sponge cake, press them lightly and dust with icing sugar.
Place the chocolate cream-filled Spekulatius biscuits in a cool place for at least 1 hour.