• Place the all purpose flour in a large bowl.
• Add baking powder and cinnamon powder (if using) to the bowl, mix well to evenly combine with the flour.
• Combine softened butter and sugar in a different bowl.
• Add milk and vanilla extract to the butter sugar mixture and mix well to combine.
• Add the prepared butter sugar mixture to the dry ingredients bowl and stir well to combine with the flour mixture. Make sure there is no dry flour left at the bottom of the bowl.
• Add the rainbow sprinkles also to the bowl and mix well to combine evenly, knead well with your hands to form the cookie dough.
• Let the cookie dough chill in the refrigerator for about 30 minutes.

To bake the cookies:

• Preheat oven to 350 degree Fahrenheit.
• Prepare a large baking sheet by lining with parchment paper.
• To make the cookies, make small balls out of the cookie dough and place the dough balls in the baking sheet (if the dough is sticky, you may apply a little oil to your palms to make the job easier).
• The cookies will spread as they bake so I recommend placing only 8 cookie balls at a time in the baking sheet (you can bake the remaining cookies in a second batch).
• Make sure to leave enough space between the cookie balls.
• Once the cookie balls are arranged in the baking sheet, place the baking sheet in the preheated oven and bake the cookies for 12 to 13 minutes until they are almost done.
• After the baking time, immediately tansfer the cookies from the hot oven to avoid over baking.
• Once the cookies are right out of the oven they are too hot and too soft in texture, but the cookies will continue to harden as they cool down so make sure to wait until they are cooled so you can enjoy them with a cup of coffee, milk or tea as you like!