[header] How to make stained glass window cookies [title] Preheat the oven to 350 degrees f (180 degrees c). [title] Sift together flour, baking powder and salt. [title] In a large bowl, cream together the butter, shortening and sugar. 
[title] Add vanilla, eggs and milk to combine. [title] Add 2 1/2 cups of the flour mixture, then add more until the dough starts to come away from the sides of the bowl.