Prepare for Baking: Preheat your oven to 220°C (200°C fan). Line a baking tray with parchment paper.

Make the Biscuit Dough: In a large mixing bowl, whisk together the 300g of plain flour, baking powder, and salt. Add the cold, cubed butter. Using your fingertips or a pastry blender, cut the butter into the flour until the mixture resembles coarse breadcrumbs with some pea-sized pieces of butter remaining.

Form the Biscuits: Pour in the cold buttermilk and stir with a fork until just combined into a shaggy dough. Tip the dough onto a lightly floured surface. Gently bring it together and pat it into a rectangle. Fold the dough over on itself 3-4 times. I find this lamination is the secret to getting those lovely, separate layers.

Cut and Bake: Pat the dough out to about 2cm (¾ inch) thickness. Use a 6-7cm round cutter to cut out the biscuits. Press the cutter straight down without twisting to ensure a good rise. Place the biscuits on the prepared baking tray and bake for 12-15 minutes, or until tall and golden brown on top.

Brown the Sausage: While the biscuits are baking, place a large, heavy-based frying pan or skillet over a medium-high heat. Add the sausage meat and cook for 8-10 minutes, breaking it up with a wooden spoon, until it's thoroughly browned and cooked through. Do not drain the fat!

Make the Gravy Base (Roux): Reduce the heat to medium. Sprinkle the 40g of plain flour over the cooked sausage and its rendered fat. Stir continuously and cook for 1-2 minutes to toast the flour. This step is vital for avoiding a raw flour taste and is the foundation of a good roux-based sauce.

Add the Milk: Gradually pour in about a quarter of the milk, whisking or stirring vigorously to create a smooth, thick paste. Once smooth, slowly pour in the remaining milk while continuing to stir, ensuring no lumps form.

Simmer and Thicken: Bring the gravy to a gentle simmer. Let it bubble away gently for 5-8 minutes, stirring occasionally, until it has thickened enough to coat the back of a spoon. If you’re using it, stir in the double cream now.

Season Generously: Season the gravy with the black pepper, salt, and the pinch of nutmeg. Taste and adjust if necessary. The gravy should be noticeably peppery.

Serve Immediately: To serve, split the warm biscuits in half. Place them on a plate and ladle the hot sausage gravy generously over the top. Serve straight away.