Soft date cake with walnuts

Name: Soft date cake with walnuts
Prep time: 5 min
Cook time: 1 h 10 min
Total time: 1 h 10 min
Yield: 10 slices
Ingredients: 220 g butter; 220 g plain flour; 100 g walnut halves; 190 g pitted dates; 190 g water; 1 tsp baking powder; 1 tsp bicarbonate of soda; 1 tsp ground cinnamon; 1 tsp sea salt; 1 egg; 1 tsp natural vanilla extract; 165 g white sugar; 140 g date syrup