Place flour, baking powder, baking soda, sugar, and salt in a mixing bowl fitted with a paddle attachment. On low speed, add cubed butter, then cream. Add rosemary and blueberries. Mix should just come together, you do not want to overmix.
Remove from bowl and wrap in plastic. Chill for 30 minutes.
Preheat oven to 3705degrees F (190 C).
On a lightly floured surface, roll the dough out to about ½ inch thickness. Cut in desired shapes.
Place dough on a cookie tray, 1 inch apart from each other.
Place tray in freezer for 10 minutes (you want the pastry to be cold before baking).
Bake for 15-20 minutes, or until edges are golden brown. Sift some powdered sugar over the top and you’re good to go!