Lightly butter a 9" x 13" x 2" inch baking pan. Set aside.
Place the butter in a large pot, and melt over low heat. Add the marshmallows and stir continuously until completely melted.
Stir in the ground freeze-dried strawberries until well combined.
Remove the pot from the heat and immediately add the rice cereal. Stir until the cereal is well coated with the marshmallow mixture.
Transfer the mixture to the prepared pan. Using a piece of wax paper or a buttered spatula, press down firmly and evenly.
If desired, sprinkle the top with more freeze-dried strawberries and press down gently to adhere.
Allow the treats to cool at room temperature for about an hour or until set. (You can speed up this process by placing them in the refrigerator for 30 minutes.)
Once set, cut into squares or desired shapes and serve.
Notes
*Different brands come in different size bags. Anything in this range will work, although more marshmallows means softer, gooier treats.
Store in an airtight container at room temperature for 5 days.