Prepare potatoes and place into the Varoma dish. Set into position above the water in the Thermomix bowl. Steam 30 min/Varoma/speed 3. Check for 'doneness'. If they are not easily crushed with a fork, keep steaming until they are.
Drain bowl, cool potatoes over hot bowl, with the Varoma lid off.
Tip potatoes into the Thermomix bowl and mash 10 sec/speed10.
Add baking powder, salt and pepper, nutmeg, 75g of the sugar, eggs, milk, EVOO and zest to the Thermomix bowl and blend 10 sec/speed 6. Stop and scrape down sides of bowl. Repeat, scrape, repeat! Make sure this mixture is silky smooth.
Add flour a third at a time and combine, 10 sec/Interval/dough setting. Add each remaining 1/3 and repeat, until finally kneading for 1 min/Interval/dough setting.
Combine remaining sugar with a good dash of additional salt and pepper in a wide mouthed bowl and set aside.
Tip batter into a piping bag with a 1cm round nozzle and pipe donuts onto 10cm squares of oiled baking paper. Heat enough oil in a small circumference deep saucepan to cover the donuts when frying or use a deep fryer as per manufacturers instructions.
Heat oil to approximately 170°C not going above 180°C (keep checking). Fry donuts one or two at a time by submerging the paper with the donut on it into the oil then removing the piece of paper with tongs and discarding. Cook about 2 minutes per side until quite dark golden. Remove with a slotted spoon and toss in the sugar salt and pepper mixture whilst still hot. Place on a wire rack to cool enough to eat! Best served the day they are made.