Piernik (Polish honey cake)

Name: Piernik (Polish honey cake)
Prep time: 20 min
Cook time: 2 h 50 min
Total time: 2 h 50 min
Yield: 12 portions
Ingredients: 3 cinnamon quills; 3 star anise; 1 tsp ground allspice; 1 tsp whole black peppercorns; 1 tsp whole cloves; ¾ tsp coriander seeds; ¼ tsp caraway seeds; 3 tsp ground nutmeg; 3 tsp ground ginger; 2 ½ tsp ground cardamom; 250 g dried pitted prunes; 50 g walnuts; 300 g plain flour; 140 g unsalted butter; 150 g honey; 150 g brown sugar; 2 eggs; 120 g Greek-style natural yoghurt; 80 g jam; 2 tbsp grapeseed oil; 1 ½ tsp bicarbonate of soda; 2 tsp cocoa powder; 100 g dark chocolate; 80 g pouring (whipping) cream