In a large mixing bowl, add sugar and lemon zest. Use your finger to massage the zest into the sugar. Whisk in the flour, tea leaves, baking powder, and salt. Carefully fold in blackberries with a wooden spoon or spatula. Cut in butter with a pastry cutter or your fingers until a crumbly sand-like mixture forms.

Drizzle over cold milk and vanilla extract. Use a wooden spoon or spatula to combine until the dough starts to come together. Once it gets too thick to stir with a spoon, use your hands to carefully form it into a ball. Form and press dough into a mound. Do not over-knead or the scones will be dense. Tightly wrap in plastic wrap and refrigerate for 20 minutes.

Preheat oven to 400°F. Line a baking sheet with parchment paper. Form dough into an 8" disc. Cut disc into 8 wedges. Lightly whisk egg with 1 tsp water. Distribute on baking sheet and brush with egg wash and sprinkle over raw sugar.

Bake for 18-20 min. or until tops are golden brown. Add blackberries to a fine mesh sieve. Place over a bowl and use a spoon to mash the berries until there is ~½-1 tsp juice in the bowl. Discard berries. Whisk in powdered sugar, milk, and vanilla until a smooth vibrant icing forms. Drizzle icing over cooled scones and enjoy.