Boil the new potatoes in boiling water until they are tender. Drain, leave to cool and slice into discs.
Cut the asparagus into bite-sized portions. Cook in boiling water until it is tender. Drain and leave to cool.
Whisk the eggs and add a splash of milk. Add salt and pepper to taste.
Put a frying pan on a medium hob and add the oil. Wait for the oil to heat up and add the new potatoes. Toss around in the pan for 5 minutes until they start to get crispy and begin to turn golden brown in colour.
Pour over the eggs and sprinkle over the feta cheese and freshly snipped thyme. Wait for 8-10 minutes until the eggs have almost set.
Pop under a hot grill to cook the top of the frittata (Check your frying pan is suitable for oven use).
Turn out onto a plate and cut into thick slices.