Browned Butter Savoury Sweet Potato Casserole

Step 1: Preheat the oven to 180°C/350°F.

Step 2: Place the potatoes on a foil-lined tray. Bake for 1 hour 15 minutes for small potatoes or 1 hour 40 minutes for large ones, until a knife can be easily inserted into the centre.

Step 3: Cool the potatoes until they can be handled while still piping hot inside, or use a tea towel to handle them.

Step 4: Meanwhile, place the butter in a large saucepan over medium heat.

Step 5: Once the butter has melted and starts to foam, add the sage leaves. Cook for 1 minute or until golden brown, then fish the leaves out through the foam and drain them on paper towels. They will crisp as they cool.

Step 6: Continue cooking the butter until the foam dies down and you see black bits on the bottom of the pan. It will smell nutty.

Step 7: Strain the butter through a paper towel-lined sieve; you should have about 180 ml.

Step 8: Crumble the sage leaves in your hand, chopping them if they are not fully crisp, and place them in a bowl.

Step 9: Add 1/4 cup browned butter, the panko, parmesan, garlic, salt and pepper. Mix.

Step 10: Cut slits down the middle of the potatoes, then scoop the flesh into a bowl.

Step 11: Add 1/4 cup browned butter, the sour cream, parmesan, salt and pepper. Mash, or use an electric beater, until smooth. If using a food processor, take care not to overprocess or the potato will become gluey.

Step 12: Place half the potato in a 2-litre (2-quart) baking dish. Use a spoon to make swirls across the surface to catch the butter, then drizzle over 1/4 cup browned butter. Cover the butter pools with the remaining potato, disturbing the butter as little as possible.

Step 13: Sprinkle over the topping. Bake for 25 minutes, until the top is golden brown and the edges are bubbling.

Step 14: Sprinkle with the crumbled bacon, then bake for a further 5 minutes. If you have any leftover butter, drizzle it over before serving.