Begin by warming your oven to 350°F (175°C), and meanwhile, cover your baking tray with parchment paper to prevent sticking.
In a large bowl, cream the butter and sugar together until light and fluffy. Then, add the egg and vanilla extract, mixing well until the ingredients are fully combined.
In a separate bowl, sift together the flour, baking powder, salt, and cinnamon if you choose to use it.
Slowly mix the dry ingredients into the wet blend until they are well combined. Mix gently until a smooth dough forms, but be careful not to overmix.
Scoop portions of the dough and shape them into half-moon forms on the prepared baking sheet. Ensure the cookies are spaced apart so they can expand slightly during baking.
Bake in the preheated oven for 12 to 15 minutes or until the edges turn lightly golden.
Carefully take the cookies out of the oven, then transfer them to a cooling rack and let them rest until fully cooled. If desired, dust with powdered sugar before serving.