Melt the butter in a large wok or frying pan. Add the garlic and chilli and cook, stirring, for 5 minutes until softened.
Add the spring greens and herbs and stir-fry for 3-4 minutes until the greens are just tender. If the greens start to stick to the wok, just add a dash of water rather than extra butter – the steam will help them cook. Serve garnished with the extra fresh herbs.