Preheat your oven to 400°F. While it heats, cube the cold butter and cut the rhubarb into 1/2-inch pieces and quarter the strawberries. Zest the lemon and measure out all dry ingredients. This prep work ensures everything is ready when you need it and prevents the butter from warming up during assembly.

In a food processor, pulse together the flour, baking powder, and salt until combined. Add the cold cubed butter and pulse until the mixture resembles coarse breadcrumbs with some pea-sized pieces of butter remaining. This technique keeps the butter cold, which creates the tender, flaky layers that make scones special.

Transfer the flour mixture from Step 2 to a large bowl and stir in the granulated sugar, ground cinnamon, lemon zest, rhubarb, and strawberries until evenly distributed. Be gentle when folding in the fruit to avoid breaking the strawberries into tiny pieces. I like to toss the fruit with a bit of flour first—it helps them stay suspended throughout the dough rather than sinking to the bottom.

Pour 3/4 cup of milk into the fruit mixture and gently stir with a fork just until a shaggy dough forms—don't overmix or the scones will become tough. Turn the dough onto a lightly floured surface and gently bring it together with your hands. Pat it into a 10-inch circle about 3/4 inch thick, then cut it into 8 wedges like a pizza. I find it helpful to use a bench scraper to cleanly cut through without squishing the dough.

Place the 8 scone wedges on a parchment-lined baking sheet, spacing them about 2 inches apart. In a small bowl, whisk together the egg with 1 tbsp water to make an egg wash. Brush the egg wash evenly over the top of each scone, which will help them bake to a beautiful golden-brown color.

Bake for 18-20 minutes until the scones are golden brown on the edges and a toothpick inserted into the center comes out clean. Remove from the oven and let cool for 5 minutes on the baking sheet before transferring to a wire rack to cool slightly.

While the scones are still warm, whisk together the sifted icing sugar, 2 tbsp milk, and vanilla extract until smooth and pourable. Drizzle the icing over the cooled scones in a decorative pattern. The icing will set slightly as the scones cool, creating a sweet glaze that complements the tartness of the rhubarb and strawberry.