Roasted Banana Ice Cream

Name: Roasted Banana Ice Cream
Ingredients: 200 grams (7 ounces) raw unsalted cashew nuts; water for soaking; 450ml (15 fluid ounces) water; 4 medium large ripe bananas, peeled and sliced into half a centimeter slices; 2 tbsp coconut oil; 2 tbsp dark brown or muscovado sugar; 1 pinch of salt; 150 (5.3 ounces) grams sugar; 4 tbsp water; 4 tbsp coconut oil; 1 tsp salt; 1 x 400ml (13.5 ounces) tin coconut cream; ½ tsp ground cinnamon; ½ tsp vanilla extract; 50g (1.75 ounces) chopped walnuts, toasted (optional); 50g (1.75 ounces) dried banana chips (optional)