Preheat your oven to 350°F (175°C). Line two baking sheets with parchment paper or silicone mats.
In a medium bowl, whisk together the flour, baking soda, salt, lemon zest, and cinnamon (if using). Set aside.
In a large bowl, cream together the softened butter and granulated sugar using an electric mixer until light and fluffy (about 2-3 minutes).
Add the egg, vanilla extract, and fresh lemon juice, and mix until fully incorporated.
Gradually add the dry ingredients to the wet ingredients, mixing until just combined.
Gently fold in the blueberries, being careful not to mash them (especially if you’re using fresh blueberries).
If the dough seems too soft or sticky, you can chill it in the fridge for 15-30 minutes to make it easier to scoop.
2. Shape the cookies:
Use a spoon or cookie scoop to form dough balls, about 1 to 1 ½ inches in diameter, and place them on the prepared baking sheets. Leave about 2 inches of space between each cookie to allow for spreading.
Flatten each dough ball slightly with the back of a spoon or your fingers.
3. Bake the cookies:
Bake in the preheated oven for 10-12 minutes, or until the edges are golden and the centers are set. The cookies will firm up as they cool.
Remove the cookies from the oven and let them cool on the baking sheets for 5 minutes before transferring them to a wire rack to cool completely.
4. Make the lemon frosting:
In a small bowl, beat together the powdered sugar, softened butter, lemon juice, and lemon zest until smooth and creamy.
If the frosting is too thick, add heavy cream one teaspoon at a time until you reach your desired consistency (it should be spreadable but not runny).
Taste and adjust the lemon juice or powdered sugar to make it as tangy or sweet as you like.
5. Frost the cookies:
Once the cookies are completely cool, spread a generous layer of the lemon frosting on top of each cookie.
For an extra pop of flavor, you can sprinkle a little more lemon zest or a few fresh blueberries on top of the frosting.
6. Serve and enjoy:
Let the frosting set for a few minutes before serving. Enjoy your refreshing Blueberry Lemon-Frost Cookies with a cup of tea or coffee!
