Ingredients
800g waxy potatoes, peeled 
30g butter or vegan butter plus 1 tsp 
4 eggs (optional) 
2 tbsp flavourless oil 
Salt 
Pepper 

Ingredients for the ancho chilli chutney 
1 tsp cumin seeds 
1 dried ancho chilli 
olive oil 
1 red onion, finely chopped 
2 cloves of garlic, finely chopped 
1 thumb-sized piece of ginger, grated 
500g ripe cherry tomatoes 
50g caster sugar 
150ml red wine vinegar 
1 lime, juiced 
Salt and pepper 

Method
Start with the chutney.  Put the cumin seeds and chilli in a dry frying pan and toast for a couple of mins until you can smell the aromas.  Once toasted, either put in a spice grinder or in a pestle and mortar and grind.  

Put the frying pan back on the heat, and add a tbsp of olive oil and fry the onion, garlic and ginger over a medium heat until soft and translucent.  Add the tomatoes, the spices, the sugar, salt, pepper and red wine vinegar. Bring to the boil and cook until the tomatoes are soft and split - about 10 mins.  With the back of a spoon gently burst the tomatoes, you want the seeds and juice to come out but the tomatoes to not be mush.  Gently mix and cook just until sticky - another few mins. 

Coarsely grate the potatoes and season with salt and pepper.  Place the grated potatoes into a clean tea towel, gather it up, twist the tea towel and keep twisting to squeeze as much moisture as possible out of your potatoes. Keep twisting and squeezing until no more liquid is being extracted.  You will be amazed at just how much comes out. 

Heat half the butter in the frying pan until foaming and then add the grated potato, flattening as you do either with your hand or a spoon so the top of the potato is smooth and the potato packed down.  Cook for several minutes without touching to let it set.  Now gently give the pan a shake to check it is not stuck to the bottom, if it is, take a knife and gently move around unsticking the potatoes without breaking so that the rosti is loose.   

Continue to cook over a medium-low heat for about 10 mins until the bottom looks golden and crisp. To turn the rosti over, place a large plate over the top of the pan, essentially what you want to do is firmly hold that plate against the pan while you turn the pan over, the rosti will now be on the plate.  You need to do this quickly and confidently to stop any breakage. 

The golden bottom side of the rosti should now facing up on the plate. Add the remaining butter to the pan and when foaming you need to carefully slide the rösti back into the pan, golden side up.  Cook for another 10 minutes until both sides are golden and the potatoes cooked.  

Put the pan back on a medium heat and put 2 tbsp vegetable oil and 1 tsp of butter and crack into the pan the eggs.  If your pan is small you may need to work in batches of 2.  Cook the egg until the white is set and then gently tipping the pan towards you, take a spoonful of the hot buttery oil and pour over the yolk, this should just seal the yolk.  If you like your yolk to be fully set rather than soft then cook a little longer.   

Put a quarter of the rosti on to the plate and place a large spoonful of the chutney over the rosti and top with the fried egg. 

Taken from Anna Jones, One Pot, Pan, Planet