The prob with sprouts is it is not cold enough in OZ, my grand dad used to grow a few plant of them in Switzerland and collect them after they had frost marks on them, I loved it was so soft and not bitter at all, just boiled and then pan fried in butter with speck (euro bacon). Was a meal by it self, or with a sweet sauce to be side dish to venison!
I tried to freeze it and cook but they stay bitter and hard!