Brunch is good. Breakfast and lunch. All in one. It should be plentiful, delicious and life saving. And as the name suggests, it should be between breakfast and lunch. 
One thing I noticed here in Stockholm is that many think brunch should be taken at around 10am. Isn't that breakfast? Anyway, if you are like me, you'd show up for brunch at some point around noon. Which is a good thing here because most tables will be available since most will be done by then. Probably already planning a 'late' 5pm Sunday dinner. 
Anyway, a great place to go for proper brunch is Bakverket, on Bondegatan. Yoghurt, all kinds of breads, jam, salads, cheeses.. Everything needed for an epic brunch. It's usually very crowded, so patience is required, but the wait is well worth it. The coffee is strong and well prepared, the service efficient and the crowd is a classic Söder crowd of young families, art-director looking teenagers and couples. Brunch is good. Even for breakfast.