Preheat and prepare your tin. Set the oven to 190°C (170°C fan) and line a 12-hole muffin tin with paper cases. While it heats, zest your oranges—notice the fine, oily mist that releases into the air; that’s the promise of brightness to come.

Whisk the dry ingredients. In a large bowl, sift together the flour, caster sugar, baking powder, bicarbonate of soda and salt. The mixture should feel light and cloud-like as you stir it with a whisk. Set aside.

Blend the wet ingredients. In a separate jug, whisk the oil, buttermilk, eggs, orange zest, orange juice and vanilla extract until the liquid is pale and completely combined. The colour will shift to a soft, creamy yellow, and the scent of orange will become noticeably stronger.

Combine gently. Pour the wet mixture into the dry ingredients. Using a spatula, fold together with just a few broad strokes. The batter should look lumpy and slightly streaky with flour—do not overmix, or the muffins will become tough. A few floury patches are perfectly fine.

Fold in the cranberries. Tip the cranberries onto the batter and fold them in with two or three turns. You’ll hear a soft squelch as they distribute, and the batter will take on a few pinkish streaks. The mixture should now be thick and scoopable, not runny.

Fill the cases and top. Divide the batter evenly among the 12 paper cases—each should be filled to just below the rim, almost full. Sprinkle a generous pinch of demerara sugar over each one. The sugar will catch the heat and turn into a delightfully crunchy, caramelised top.

Bake until golden and fragrant. Place the tin in the centre of the oven and bake for 22-25 minutes. At the 20-minute mark, the kitchen will fill with a deep, toasty orange aroma. The muffins are ready when the tops spring back to a gentle touch and a skewer inserted into the centre comes out clean, save for a few moist crumbs.

Cool and enjoy. Let the muffins rest in the tin for 5 minutes—they’ll be too tender to move immediately. Then transfer them to a wire cooling rack. The tops should be a deep golden brown, and you’ll see tiny ruby flecks of cranberry peeking through. Let them cool for at least 10 minutes before serving, if you can wait that long.