In your mixer's bowl, combine the butter, sugar, and lemon zest. Mix until they've creamed together.
Add the egg (and food coloring, if you want) and mix.
Add the lemon juice and lemon extract and mix further. The dough will curdle; don't worry about it.
Add the flour, baking powder, and salt, and continue mixing until it's well incorporated.
Cover the dough in the mixing bowl and chill in the fridge for 30 minutes.
Remove the dough from the fridge and, using a cookie scoop, scoop out balls of dough. You can get anywhere from 10-14 depending on how large you want your cookies and how large your cookie scoop/spoon is.
Form the dough into globs and arrange on a cookie sheet. Put this in the freezer for 30 minutes.
Preheat oven to 350 degrees.
Ensure the dough balls are as round as possible, then bake for 13 minutes. The cookies will seem under-done; that's intentional to keep them soft and moist.
Remove cookies from the oven and let cool completely. Dust with powdered sugar if you want, then enjoy.