Method

• Preheat oven to 200°C and brush two 12-cup non-stick mini muffin tins with the oil. Ensure the seam between the base and the side of each cup is well-oiled as that’s where the batter tends to stick.
• Cut the onions into chunks. Blitz in a food processor for 30 seconds until very finely chopped, scraping down the sides as needed.
• Leave the onion in the food processor bowl and swap the chopping blade for the medium grating/shredding disc.
• Cut the potatoes into 4 - 6 chunks and grate in the processor.
• Tip the vegetables into a large sieve. Over the sink press them with your fingers to squeeze out as much of the starchy liquid as possible, mixing the onion and potatoes together as you go (the onion juice helps prevent the potato from turning orange or brown). Leave to drain further while you make the batter.
• Beat the eggs with the seasonings, flour and baking powder in a large bowl.
• Give the vegetables another good squeeze to extract more liquid then add to the eggs and mix well with a fork.
• Divide the mixture between your muffin tins – I use a small cookie scoop to do this. Don’t be tempted to pack them too tight or press the tops down - they should be domed and slightly craggy for maximum crispiness.
• Bake in the centre of the oven for 20-25 minutes or until rich golden brown then cool on a rack for 5 minutes. Run a spoon around the edges and remove them from the tin.
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• To make ahead:
• Bake as above but only about 15 minutes - until pale gold. Cool then refrigerate overnight, or freeze on a baking tray for at least an hour then transfer to a plastic bag and seal. Half an hour before serving, preheat oven to 180°C and arrange them on a baking tray. Reheat for 8-10 minutes from chilled, 10-15 minutes from frozen, until hot inside and a rich brown on top.