Slice blackberries in half and place in medium bowl. Sprinkle with sugar, honey powder, lime zest, and salt. Gently mix. Cover and place in fridge to macerate for at least 2 hours or overnight.
While the berries are doin’ their thing, it’s biscuit time! Heat oven to 400°F. Line baking sheet with parchment paper.
In a large bowl, whisk together flour, honey powder, baking powder, and salt.
In a small bowl, whisk together egg, vanilla, and cream.
Add cold, cubed butter to flour mixture, tossing around gently to coat. Using a pastry blender or fork, quickly cut in butter until mixture resembles coarse crumbs.
In the centre, make a well, then pour in the wet ingredients. Mix just until dough comes together.
Place dough on lightly floured surface. Knead a couple of times, then pat dough into a slab that is roughly 7" by 4" and 1" tall. Cut into six equal pieces.
Place shortcakes on baking sheet. Brush tops with cream and sprinkle with sugar.
Bake for 15–20 minutes or until lightly golden.
Cool biscuits on baking sheet for a couple minutes, then transfer to wire rack and allow to cool completely.
When you’re just about ready to serve your shortcakes, place metal mixing bowl and whisk attachment in freezer for 15 minutes.
While those items are chilling, cut shortcakes in half. Gently mix berries.
In the chilly bowl of a stand mixer fitted with cold whisk attachment, whip cream, honey powder, and confectioners’ sugar until soft peaks form. (At the very beginning, keep an eye on it and scrape down sides as necessary since the honey powder tends to stick at first.)
To assemble, place shortcake bottoms on plates. Top with some berries and juice, whipped cream, and biscuit top. Enjoy immediately.