Preheat the oven to 400F. Line a large baking sheet with parchment paper. Place the butter in the freezer for about 10 minutes to ensure it’s very cold.
In a large bowl, whisk together the flour, salt, baking powder, baking soda, and caster sugar.
In a separate bowl, whisk the egg. Add the blended cottage cheese, lemon juice, and lemon zest, stirring until smooth.
Pour the wet mixture into the dry ingredients and mix gently until just combined. Avoid overmixing.
Remove the butter from the freezer and grate it directly into the dough. Lightly knead just enough to evenly distribute the butter throughout.
Gently fold in the raspberries, being careful not to crush them too much. Tip: If using very soft raspberries, you can freeze them for 15–20 minutes beforehand to make folding easier. If the dough feels too dry, add a small splash of lemon juice or water.
Transfer the dough to a lightly floured surface and shape it into an 8-inch circle. Cut into 8 wedges and carefully place them on the prepared baking sheet.
Whisk together the egg and water, then brush the tops of the scones.
Bake for 18–20 minutes, or until lightly golden. Allow the scones to cool on the baking sheet before serving.
Stir together the lemon juice and powdered sugar until smooth. Drizzle over the cooled scones before serving.