Line a greased tart tin with pastry and blind bake for 10 minutes. Remove the baking beads and bake for a further 2 minutes. Remove from oven and set aside.
Whisk 5 eggs together with the milk and sour cream until combined. Grate a pinch of fresh nutmeg and whisk again.
Pour into your prepared tart tin and back for 25 minutes. You tart will fluff up during the cooking process but it will settle down once you remove it from the oven.
Top warm tart with halved cherry tomatoes, crumbled feta and fresh basil. Serve and enjoy.