Set out butter for the honey butter so that it can soften while you prepare the scones.
Pulse lavender and granulated sugar in spice grinder or food processor until lavender is chopped well.
Pour sugar mixture into a large bowl, then add lemon zest. Using your fingers, rub lemon zest, sugar, and lavender together until thoroughly combined.
Add flour, baking powder, baking soda, and salt. Whisk together.
In a small bowl, mix together lemon juice, cream, vanilla, and egg. Place in fridge.
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.
Turn dough out onto lightly floured surface. Knead 8–10 times until smooth, adding a little bit of flour, if necessary.
Shape dough into a 7-inch circle. Using a lightly floured knife or bench scraper, cut circle into 8 scones.
Line baking sheet with parchment paper. With lightly floured hands, separate scones and place on baking sheet.
To make the egg wash, in a small bowl, beat together one egg and one tablespoon of cream. Brush tops of scones with egg wash. Sprinkle with turbinado or sparkling sugar. Place baking sheet in fridge to keep dough cold while oven warms up.
Heat oven to 400°F.
Bake 18–20 minutes or until scones are lightly browned. While scones are baking, make your honey butter by mixing the softened, salted butter and honey.
Transfer scones to a wire rack and allow to cool for 10–15 minutes before serving with honey butter.