Line a 12-hole muffin tin with muffin papers.
Place sugar into Thermomix bowl and mill 8 sec/sp 8.
Add flour, baking powder, salt and nutmeg. Turbo/1 sec x 2.
Remove to a large bowl.
Place eggs, buttermilk, oil and vanilla into bowl and mix 10 sec/sp 5.
Gradually mix liquid ingredients into dry ingredients until just combined. Leave any little bits of flour.
Fold in the blueberries (unless frozen, then fold in just before filling muffin tins).
While batter is resting, turn oven on to 220C.
When oven is ready fill muffin papers with mixture – a centimetre from the top of the papers.
Bake 7 minutes at 220C.
Turn oven to 175 and continue cooking for 22-25 minutes.
Allow muffins to cool in pan for about 5 minutes before removing to a wire rack.