Peas! 
Lasagne night in the Hashbrown household and we are reminiscing about the time my DH (then bf) made a lasagne and not only out peas in the mince mixture, but served them as a side too.
I literally did consider strongly ending our relationship at that point.
To this day, he maintains it's a normal thing to have in/with lasagne?!
AIBU?
As a side note, I always serve it with mixed salad and either garlic bread or if I'm being proper porky, chips too!