In a medium bowl, whisk together 5 cups of the flour, baking soda, and baking powder. Set aside.

In the bowl of a stand mixer fitted with the flat beater attachment, combine the room-temperature butter and granulated sugar.

Beat on medium speed for approximately 3 minutes, or until the mixture is light and fluffy.

Scrape down the sides of the bowl with a rubber spatula as needed.

Add the eggs, one at a time, beating well after each addition until fully incorporated.

Add the vanilla extract and light sour cream.

Beat on low speed until the mixture is fully combined.

Add the prepared dry ingredients to the wet ingredients.

Beat on low speed for approximately 30 seconds, or until just combined, scraping down the bowl as necessary.

Add the remaining flour, 1/4 cup at a time, as needed, until the dough reaches a consistency suitable for rolling. Do not exceed the remaining 1 cup of flour.

Divide the dough into two equal portions.

Flatten each portion into a rectangle approximately 1 1/2 inches thick.

Wrap each dough portion tightly in plastic wrap.

Refrigerate the dough overnight.

Preheat the oven to 425°F.

Line two large baking sheets with parchment paper or coat them lightly with nonstick cooking spray. Set aside.

Generously flour a clean work surface and rolling pin.

Roll one portion of chilled dough to 1/4-inch thickness.

Using a 2 1/2-inch round cookie cutter, cut the dough into circles.

Transfer the cookie rounds to the prepared baking sheets, leaving space between each cookie.

Repeat with the remaining dough, re-rolling scraps as needed.

Bake for 7 to 8 minutes, or until the cookies are set and pale golden.

Immediately transfer the baked cookies to a wire rack.

Allow the cookies to cool completely before frosting.

To prepare the frosting, place the room-temperature butter and vanilla extract in the bowl of a stand mixer fitted with the paddle attachment.

Beat until smooth and creamy.

Gradually add the powdered sugar, mixing on low speed until incorporated.

Add the heavy cream, 1 tablespoon at a time, until the frosting reaches the desired spreading consistency.

Add food coloring, if desired, and beat until the color is evenly blended.

Spread frosting over the cooled cookies.

Immediately add sprinkles before the frosting sets.

Allow the frosting to set completely.

Store the cookies in an airtight container.

For best flavor, allow the frosted cookies to sit for several hours before serving.