Boil, steam or microwave whole potatoes for 5-8 minutes, until tender. Drain and when cool enough to handle, cut into thick slices.
Mix together oil, lemon juice, garlic and chilli in a large bowl. Add potato, while still warm; gently toss to coat then set aside.
Blanch broad beans and peas in a large pan of boiling water. Drain, then peel broad beans. Add peas, broad beans, chives and mint to potato and gently toss to combine. Serve topped with crumbled feta.