-
1
Heat the oven to 180 °C. Place the squash halves cut-side down on a lined baking tray and roast until completely tender — approximately 40 minutes. The flesh yields without resistance when pressed through the skin and the cut edges are visibly caramelised and dry.
-
2
Scoop the flesh from the skin and pass it through a mouli or mash it thoroughly to a smooth, dry purée. Spread it across the tray for a few minutes to allow any remaining steam to escape. The purée should hold its shape on a spoon without slumping.
-
3
Transfer the purée to a bowl. Fold in the crumbled amaretti, Grana Padano and nutmeg. Add the mostarda last, folding it through gently so that the pieces remain distributed but do not break down entirely. Taste: the mustard heat must be detectable but not dominant — this is where the dish lives or dies, and a heavy hand with the mostarda will unbalance every other element.
-
4
Grease a terracotta baking dish generously with butter, ensuring the sides are well coated. Pour in the squash mixture and smooth the surface. Transfer to the 180 °C oven and bake for approximately 35 minutes. The top is lightly and evenly golden, and the centre no longer wobbles when the dish is moved.
-
5
Remove from the oven and leave to cool to room temperature before serving. The texture firms as it cools and the agrodolce flavours settle and integrate. The surface should feel set and dry to a light touch at the centre.