Butternut rings filled with savoury mushrooms

This is one of those dishes that began as a bit of thrift. Once you have cut rounds out of a butternut squash, you are left with the centre circles, and rather than bin them, the recipe grates them into the filling. That little trick means nothing goes to waste, and it gives the mushrooms a sweet, soft backbone that holds everything together without any cheese or cream.

A word about the squash itself. Butternut is one of the winter squashes, and its flesh is dense and naturally sweet, with plenty of fibre and vitamin A from its orange colour. It keeps well in a cool, dry place for weeks, which is why it has been a kitchen staple through so many autumns. If you are working with a very firm one, a sharp vegetable peeler and a steady hand will save you a lot of grief. Leaving the skin on the rings is fine too, since it softens in the oven and adds a little colour to the plate.

Mushrooms ask for patience. They release a lot of water as they cook, so give them the time to dry out in the pan before you think about adding anything else. Those few extra minutes on the heat turn a watery mixture into something rich and savoury. The porridge oats do a quiet job here as well: they soak up the juices and give the filling a little body, so it sits neatly in each ring rather than sliding off.

Sage is the herb that makes this taste like a proper roast. Chop the leaves finely for the filling, then save a few whole ones for frying. They go crisp in a very short time, and they are the first thing people reach for on the plate. Keep an eye on them, because the moment they stop sizzling they can turn from crisp to bitter.

For leftovers, the filling keeps in a sealed container in the fridge for a couple of days and makes a decent stuffing for a baked potato or a spoonful beside scrambled eggs. Cooked rings can be reheated gently in the oven, though they are best eaten the same day. If you have a glut of mushrooms in the fridge, this recipe is an easy way to use them up.

To serve, I like it simply: a plate of steamed long green beans with a squeeze of lemon, or some strips of sweet pepper that have been softened in the same pan. A spoonful of wholegrain mustard on the side works nicely too.

If you want more ideas from the same kitchen, the Wild Mushroom and Herb Lattice Pies use a similar earthy filling in a different way, and the Golden Butternut Squash Soup is a gentle way to make the most of the squash if you have one left over. For something heartier, the Comforting mushroom and pearl barley risotto carries the same mushroom flavour into a bowl you can eat with a spoon.