Preheat oven to 400°F (200°C). Line a baking sheet with parchment paper.

In a large mixing bowl, whisk together the flour, granulated sugar, baking powder, and salt.

Add the cold, cubed butter to the dry ingredients. Using a pastry blender, two forks, or your fingertips, cut the butter into the flour mixture until it resembles coarse crumbs with some pea-sized pieces of butter remaining.

Pour the 1/2 cup cold heavy cream into the flour mixture. Mix with a fork or spatula just until the dough comes together. Be careful not to overmix.

Gently fold in the diced fresh strawberries until evenly distributed.

Turn the dough out onto a lightly floured surface. Gently pat or roll the dough into an 8-inch round, about 3/4 to 1-inch thick.

Using a sharp knife or a bench scraper, cut the round into 8 wedges. Alternatively, use a 2.5-inch round cutter to cut out scones, re-rolling scraps once.

Carefully transfer the scone wedges to the prepared baking sheet. In a small bowl, whisk the egg with 1-2 tablespoons of heavy cream to make an egg wash (if using). Lightly brush the tops of the scones with the egg wash for a golden finish.

Bake for 16-20 minutes, or until the scones are golden brown on top and a wooden skewer inserted into the center comes out clean.

Transfer the baked scones to a wire rack to cool slightly while you prepare the drizzle.

In a small bowl, whisk together the powdered sugar and 2 tablespoons of lemon juice until smooth. Add more lemon juice, a teaspoon at a time, until you reach your desired drizzling consistency.

Drizzle the lemon glaze over the still-warm or cooled scones. Serve immediately or store for later.