Begin by bringing a saucepan of salted water to a rolling boil. Add the 8oz (250g) of shelled fresh fava beans and cook for just a few minutes until they are just tender. This initial cooking time for the fava beans is pivotal, as they require slightly longer than the other vegetables to reach the perfect texture.
Once the fava beans are nearly done, add the 8oz (250g) of shelled peas and the 8oz (250g) of halved green beans to the same pot, then continue cooking for another 5–10 minutes until all vegetables are tender. The exact timing will depend on how fresh your vegetables are; younger, fresher produce will cook more quickly than older vegetables.
Once all the vegetables are cooked to your desired tenderness, carefully drain them in a colander to remove all the cooking water. Return the drained vegetables to the warm saucepan and add the 2 tbsp of butter and 2 tbsp of chopped fresh mint.
Stir gently until the butter has completely melted and is evenly distributed throughout the vegetables, coating them in a light, glossy finish. Taste the dish and adjust the seasoning with salt and black pepper as needed to suit your preference.
Serve the summer peas and beans hot while they retain their vibrant color and warmth. Transfer to a serving dish and garnish with additional fresh mint to add both visual appeal and an aromatic finishing touch that enhances the delicate flavors of the seasonal vegetables.