2Cbuttersoftened (yes, I know it's a lot. We're frosting 5 dozen cookies here)
With an electric mixer, cream the sour cream and butter at low speed; add sugar, eggs, and vanilla & mix until combined.
Gradually add the flour, baking soda, and salt to the sour cream mixture, mixing until well combined. Dough will be sticky.
Divide dough onto two pieces of plastic wrap; flatten dough into a square, wrap tightly, and refrigerate until chilled, 1-2 hours.
Preheat oven to 350 degrees.
Generously flour your counter or work surface to prevent dough from sticking. Rub flour on the rolling pin. Put one of the chilled pieces of dough on top of the floured surface and sprinkle the top of the dough with more flour.Roll the dough to an even ¼" thick all over, sprinkling with additional flour, as needed.
Dip cookie cutter in flour and cut out dough shapes. Transfer dough shapes to lined baking sheets.
Bake cookies for 8-10 minutes, Cookies are done when just set and the edges or bottoms have no color. Transfer hot cookies to a baking rack to cool completely.
Beat powdered sugar, butter, and salt in an electric mixer until smooth.
Stream in orange juice and extracts and beat until fluffy. Add more orange juice or powdered sugar as needed to thin or thicken the finished frosting.
Spread or pipe frosting on cooled cookies. Let cookies sit uncovered for a few hours to harden frosting. Store cookies in an airtight container.