Preheat and prepare: Set your oven to 190°C (170°C fan) and place a rack in the centre. In a large mixing bowl, combine the sliced peaches, 60g of the granulated sugar, the brown sugar, cornflour, cinnamon, nutmeg, and lemon juice. Stir gently with a wooden spoon until the peaches are evenly coated – you'll see the sugar beginning to draw out their juices, creating a glossy syrup around the fruit.

Cook the filling: Transfer the peach mixture to a large ovenproof frying pan or skillet over medium-high heat. Cook for 5–7 minutes, stirring occasionally, until the juices thicken and bubble around the edges. You'll know it's ready when the liquid turns from cloudy to clear and translucent, and the peaches soften slightly but still hold their shape. The aroma of warm cinnamon and caramelised fruit will fill your kitchen.

Make the biscuit topping: In a separate bowl, whisk together the plain flour, the remaining 40g granulated sugar, baking powder, and salt. Add the cold butter cubes and use your fingertips to rub them into the flour mixture until it resembles coarse breadcrumbs – you should see small, pea-sized pieces of butter throughout, which will create steam pockets and give you a light, fluffy topping.

Finish the dough: Pour in the milk and vanilla extract, then stir with a fork just until a soft, sticky dough forms. Do not overmix – a few streaks of flour are fine, and the dough should be shaggy rather than smooth. It will look lumpy and rustic, which is exactly what we want.

Assemble the cobbler: Remove the peach filling from the heat. Using two spoons, drop heaped spoonfuls of the dough evenly over the hot fruit. You don't need to spread it – leave gaps between the dough mounds so the filling can bubble up and create those beautiful caramelised edges. The dough will look pale and lumpy against the dark, glossy fruit.

Bake to golden perfection: Place the pan in the preheated oven and bake for 25–30 minutes, until the topping is puffed, golden brown, and a skewer inserted into a dough mound comes out clean. The filling should be bubbling vigorously around the edges – you'll hear it hissing and popping as it bakes. The top will smell sweet and buttery, and the fruit will have darkened to a deep amber colour.

Rest and serve: Remove the cobbler from the oven and let it sit for 5 minutes on a wire rack. This brief rest allows the juices to settle so they don't run all over the plate. Serve warm, straight from the pan – the topping will be crisp on top and soft underneath, with the peach filling thick and jammy.