Roast in the oven for 20-25 minutes, turning throughout to prevent burning. Once the cubes are soft, take them out and set aside to cool slightly.
It's important not to turn the heat up and to be patient so the rice cooks all the way through. Near the end you can add a bit more of the stock at a time, but make sure it is mostly absorbed before adding more.
Serves 2 as a main or 4 as a starter.
Sage and butternut squash is a glorious flavour combination which can be used in many delicious meals, including this one, however where the other herbs merely enhance the overall flavour, the sage can become as strong a flavour as the squash, and sometimes I think it's nice to let it stand by itself.