If using a stand mixer, fit with paddle attachment. Cream together shortening and butter until completely mixed.
Add in the sugar and beat until light and fluffy.
Add in eggs, one at a time, and beat until combined. Add in vanilla and beat until combined.
With the mixer on slow speed, add in the baking powder and flour. Mix until just combined.
Cover and chill dough for at least an hour.
Turn out dough on a floured surface and roll dough 1/8" thick. Cut cookies with desired cookie cutters. Place cookies on parchment lined cookie sheet and bake at 350 degrees for about 8 minutes or until bottom is brown and the brown is creeping up the edges. The tops of the cookies should not be shiny at all.
Allow to cool completely. Frost and decorate as desired.
Notes
These cookies don't spread too much, but if you don't want any spreading, chill cut out cookies for 5-10 minutes before baking. This is more necessary for cut-outs with finer details.
The number of cookies this recipe makes obviously depends on the size of your cookie cutters.
This dough can chill in the fridge for up to 3 days and can be frozen for a couple of months. To freeze the dough, wrap in plastic wrap and then place in a freezer safe ziplock bag.