Preheat your oven to 350 degrees.

In a large bowl, beat together butter and sugar until creamy. Add your egg, flour, salt and baking powder and beat at low speed until you have a thick and crumbly dough.

Refrigerate your dough for 20 minutes and then place on a sheet of parchment paper. Sprinkle with flour and roll to about a ½ inch thickness using a rolling pin.

Using your shamrock cookie cutter, cut out your shapes and sprinkle with green sprinkles. Using your finger tips, lightly press the sprinkles down into the cookie so that they adhere.

I hate when the sprinkles fall off a sugar cookie when I take them out of the oven!

Transfer to your cookie sheet and bake at 350 degrees for about 8 minutes, or until edges start to brown.

Once you remove from the oven, allow the cookies to cool on the cookie sheet for about 5 minutes so that they harden up a but before removing them to a cooling rack