Heat half the butter in a large frying
pan and soften the onions over a low
heat for about 15 mins until really soft –
but don’t let it brown. Add most of the
sage. Meanwhile, cook the sprouts in
a pan of boiling water for about 4 mins,
add the peas and cook for 1 min more
until just tender.
Drain, reserving a splash of the water,
then add the sprouts and peas to the
onions, along with the rest of the butter,
stirring well so that all the veg gets
coated in the butter. Add the reserved
cooking water if it looks a bit dry.
Season with lots of black pepper
and some salt. Serve with the reserved
sage on top.