Preheat the oven to 200°C/180°C fan. When it is hot, add the cherry tomatoes, drizzled with a little olive oil and sprinkled with salt and pepper. (These will take about 20 minutes and will be ready by the time the rosti are).
Wilt the spinach by pouring boiling hot water over it in a colander in the sink. Remove the excess water by placing an empty bowl on top of the spinach and pushing the liquid through the colander (the rosti will cook much better if all excess water is removed). Remove the spinach from the colander and allow to cool.
Add the peeled and grated potatoes to a bowl. Add the egg, flour, spring onion, nutmeg and chilli flakes, salt and pepper and stir well. Add the wilted and squeezed spinach and stir again, finally adding the crumbled feta and stirring briefly to incorporate.
Heat the oil in a large frying pan until hot (this is important as you really want the rosti to crisp up). Spoon the mix into the pan – forming shapes about 10cm wide. After about 3 minutes you can carefully flip each rosti. Cook for a further 3 minutes and then transfer to a large oven tray for a further 10 minutes to finish cooking (you may need to do this in batches).
Serve the rosti with the roasted cherry tomatoes on the top.
TIP These freeze well.
500g smooth potatoes (such as Desiree), peeled and roughly grated
150g cherry vine tomatoes
1 egg, lightly beaten
30g plain flour
2 spring onion, finely chopped
¼tsp nutmeg (optional)
¼tsp chilli flakes
100g feta, crumbled