Toss berries with sugar and salt. Let sit for at least 1 hour. Strain berries in a fine mesh sieve over a bowl to save the sugary liquid. Let sit to drain while you make your scone dough.
To make dough mix flour, sugar, baking powder and salt in a bowl. Add in butter cubes and rub between your fingers to break up into small pea-sized bits.
Whisk egg, cream and vanilla in a small bowl. Add wet ingredients, along with the strained berries to the butter and flour mixture. Stir to combine. Don’t over mix.
Shape dough into a roughly 8” circle. Cut into 8 wedges and arrange on an un-greased baking tray. Brush with heavy cream and sprinkle with sugar. Bake for ~18 mins and cool on a wire rack.