Make it
Roast the squash
Halve lengthwise and scrape out the seeds. Rub with oil, season and roast cut-side down at 425°F for 35–40 minutes, until just tender.
Make the sauce
Warm Boursin and cream together until smooth. Fold in half the Parmesan, spinach and red pepper flakes.
Combine
Scrape the squash into strands without crushing them. Fold into the sauce, taste for salt and return the mixture to the squash shells or a baking dish.
Brown
Top with remaining Parmesan and bake 10 minutes. Broil briefly for browned edges, then rest 5 minutes.
From the Haus
- Stop roasting while the strands still have structure. Overcooked squash releases water into the sauce.
- Add cooked chicken or crumbled sausage when this needs to become the whole meal.