Preheat the oven to 390°F (200°C), or 350°F (180°C) for fan ovens. Line a baking sheet with parchment paper.
Add the self-rising flour to a large bowl. Rub in the cold butter using fingertips until the mixture resembles fine breadcrumbs.
Pour the cold milk over the flour mixture. Stir gently until a rough dough forms.
Turn the dough onto a lightly floured surface. Knead lightly about 8 to 10 times, just until smooth.
Pat the dough into a disc about ¾ inch thick.
Flour a 2-inch round cutter. Cut straight down into the dough without twisting.
Transfer the scones to the baking sheet. Brush the tops lightly with milk.
Bake for 10 to 12 minutes, until lightly golden.
Beat the whipping cream, sugar, and vanilla until soft peaks form.
Let the scones cool until warm. Split them open and serve with whipped cream and strawberry jam.