Toast the pittas in a toaster until they’re just under-done – puffed up but not yet crisp – then leave to cool for a few mins. Meanwhile, using a fork, mash the feta in a large bowl. Stir in the herbs and lots of black pepper.
Cut a slit along one edge of each pitta, then spoon in the feta. Spread it out over the inside of the bread with the back of the spoon or a cutlery knife. Can be prepared up to 1 day ahead and kept covered in the fridge.
To serve, re-toast the pittas, cut-side up, in the toaster until the bread is just crisp, then leave to cool for 2 mins before cutting into wedges. Best eaten within 30 mins of toasting.