Now Monica Galetti can get away with writing ‘mash’ on her menu and we all know it’s not, not really. However my humble little bistro does not afford me that luxury and so the marketing of my menu must be a little more considered, shall we say; couple this with a compulsion to compartmentalise and encase anything that moves (or had moved at some point) and a potato Swiss roll makes perfect sense. It ticks other boxes too; it’s prepared in advance, it’s quantities can be upscaled or downscaled and it’s portioned individually needing only 20 mins in a hot oven when the time comes.
The inclusion of puff pastry adds substance as well as style I might add, and in this instance shop bought is perfectly adequate.
(portions in to 10)
1 x 500g pack of puff pastry
2kg potatoes, all-rounders such as Maris Piper
75g salted butter
1 x egg beaten with a fork
Peel the potatoes and halve them if necessary into evenly sized pieces.
Bring them up to the boil in a pan of cold salted water and simmer until tender. Meanwhile, clear a shelf in the fridge to make way for the resting roulade later on.
Drain the potatoes in a colander, then return them to the hot empty pan and leave them to steam themselves off for a few minutes. Add the butter to the potatoes and mash (or pass them through a ricer), adding salt, pepper and tasting as you go.
Leave the mashed potatoes to go completely cold – spread them out on a tray or a large plate to speed up the process and help dry them out.
Roll out the pastry into a rectangle (landscape), roughly the thickness of a pound coin. Tip the cold potato onto the pastry and use your hands to lightly press the mash to an even thickness, trim and tidy the edges to leave an inch border all the way around.
Take your rolling pin and gently roll the surface of the potato, filling in any bumps and hollows with the edge trimmings.
Brush the lengthways border furthest from you with the egg wash.
Starting with the edge closest to you, roll the pastry in on itself in the style of a Swiss roll, rolling away from you to finish with the egg washed edge on the underneath.
Roll the whole thing carefully onto a tray big enough to accommodate it (use a piece of cling-film as a sling/hoist if you need to), then egg wash it and park it in the fridge to firm up for a couple of hours.
Once the egg wash has dried, slice the roulade into inch thick slices and place each one on a slip of baking paper to prevent them sticking to each other. They can stay like this in the fridge for two or three days.
Bake them on their baking paper for 20 mins at 200 ⁰C, turning them over half way through to brown on both sides.