Heat the oven to 200C/180C fan/gas 6. Tip the potato and courgette slices into a large bowl and toss with the olive oil and some seasoning. Arrange in a single layer on two baking trays and roast for 25 mins until lightly golden, stirring halfway through to brown evenly.

Line a 20 x 30cm baking tin with a large sheet of baking parchment, ensuring there are no tears or cuts (where the egg might leak through). Layer the veg on the parchment, scattering most of the feta and all of the mint between the layers.

Season the egg, then pour this over the veg. Crumble over the rest of the feta. Bake for 25-30 mins until the egg is cooked and the top is golden. Leave to cool completely in the tin, then chill until needed. Will keep chilled for up to two days. Cut into squares and pack into a lunchbox or picnic hamper.