Miso noodle soup with mushrooms & ginger

Ingredients

• 12 g instant dashi
• 80 g shiro (white) miso paste
• 1 tbsp finely grated ginger
• 200 g shiitake mushrooms, halved
• 50 g oyster mushrooms, torn
• 50 g enoki mushrooms
• 1 tbsp dried seaweed
• 300 g green tea soba noodles
• 150 g silken tofu, diced
• 1 bunch English spinach, trimmed
• Thinly sliced spring onions, torn nori and roasted sesame seeds, to serve