For the Cookies:

1. Prepare one batch of sugar cookie dough. Form into a large flat disc and tightly cover with plastic wrap. Refrigerate for about one hour. 
2. Remove the dough from the refrigerator and place on a lightly floured large flat work surface. With a rolling pin, spread and flatten out the dough until it is between 1/8 and 1/4 inch thick.
3. Using a floral cookie cutter with about a 3-inch diameter, cut out shapes from the dough to make about 24 cookies. Dip the cookie cutters in flour if the dough sticks. Re-roll the remaining dough once and cut again. Discard any excess.
4. Transfer the cookie dough cut-outs to two baking sheets lined with parchment paper or silicone mats, placing 12 cookies on each baking sheet. Place the pans in the refrigerator for about 30 minutes to chill.
5. Preheat the oven to 325°F while the dough chills.
6. Remove the trays from the refrigerator and immediately bake for 8-10 minutes, depending on the thickness of the dough. They will still be pale white and soft to the touch.
7. Remove from the oven. Let stand on the baking sheets for about 5 minutes, then transfer the cookies to wire racks to cool completely before decorating.

For the Royal Icing and Decorating:

1. Prepare a double batch (about 6 cups) of royal icing with a medium-stiff consistency. Color with your desired food coloring. The icing should be able to hold its shape, like a traditional buttercream. Add more powdered sugar in 1/4-cup increments if the icing is too runny.
2. Prepare a pastry bag fitted with a #104 petal piping tip. Fill the pastry bag with the prepared royal icing, covering any remaining icing in the bowl with plastic wrap.
3. Position the pastry bag so the thinnest end of the piping tip is facing the top when you hold the pastry bag.
4. Starting with the outside border of one cookie, pipe small individual petals in a complete circle following the curves of the cut-out.
5. Moving closer to the center of the cookie, pipe a layer of smaller individual petals in a complete circle, covering the bottom half of the first layer.
6. Moving to the center of the cookie, pipe a layer of even smaller individual petals in a complete circle, covering the bottom half of the second layer and the entire center of the cookie. The cookie will now have three layers of petals.
7. Immediately and carefully place nonpareil sprinkles in the center of the cookie while the royal icing is still wet.
8. Set the cookie aside to dry. Repeat the decorating process with the remaining cookies.
9. Let the cookies sit at room temperature until the icing is completely set and hardened, about 2-3 hours.
10. Store the cookies in a single layer in an airtight container at room temperature for one week.