Preheat the oven to 180C (350F) and line a baking sheet with parchment paper.
In a bowl, combine the flour with baking soda and set aside.
Place the butter, sugar, and salt in the bowl of a stand mixer fitted with a paddle attachment (or use a bowl and a hand mixer). Beat for 2-3 minutes on medium-high, scraping the sides and the bottom a couple of times in between, until well combined, fluffy, and pale in color.
Add the egg and beat again until fully incorporated. Then, add the lemon juice, zest, and extract and beat just until incorporated.
Add the dry ingredients and mix on low until no dry ingredients are left.
Using a 3 tablespoon cookie scoop, scoop 14 cookie dough balls onto the baking sheet, leaving at least 2" or 5cm distance in between. Alternatively, make 20 cookies using a 2 tablespoon cookie scoop. If you have to work in batches, leave the rest of the dough in the fridge while the first batch is baking.
Bake for 10-12 minutes or until the cookies have spread, puffed up, formed very small cracks, and are slightly golden around the edges. Don’t let them brown!
Remove from the oven and let cool down on a baking sheet for 10 minutes. Then, transfer onto a cooling rack to cool down completely and bake the second batch, if you have one.