1-Preheat your oven to 400°F (200°C): Preheat your oven to 400°F (200°C). Line a baking sheet with parchment paper and set aside.
2-In a large bowl, whisk together 2: In a large bowl, whisk together 2 cups (250g) all-purpose flour, 2 teaspoons baking powder, and 1/4 cup (50g) granulated sugar.
3-Add 1/2 cup (115g) cold, cubed unsalted: Add 1/2 cup (115g) cold, cubed unsalted butter to the flour mixture. Using a pastry cutter or two knives, work the butter into the flour until the mixture resembles coarse crumbs with pea-sized bits of butter remaining.
4-Gently fold in the zest from 1: Gently fold in the zest from 1 large lemon and 1 cup (150g) blueberries. Be careful not to crush the berries; if using frozen, toss them in straight from the freezer.
5-Slowly add 1/2 cup (120ml) milk or: Slowly add 1/2 cup (120ml) milk or cream while stirring with a fork or spatula until the dough just comes together. It should be slightly sticky but manageable. Avoid overmixing.
6-Lightly flour your work surface and gently: Lightly flour your work surface and gently knead the dough 2-3 times to bring it together. Pat into a 7-inch (18cm) circle about 1 inch (2.5cm) thick.
7-Using a sharp knife or bench scraper,: Using a sharp knife or bench scraper, cut the dough circle into 8 equal wedges. Transfer them carefully to the prepared baking sheet, spacing slightly apart.
8-Bake for 18-22 minutes, or until the: Bake for 18-22 minutes, or until the tops are golden and a toothpick inserted in the center comes out clean.
9-Let the scones cool on the baking: Let the scones cool on the baking sheet for 5 minutes before transferring to a cooling rack. Serve warm or at room temperature.