Poppable and addictive pinwheels become even more delicious with the addition of creamy peanut butter.
Reserve about 1⁄4 cup of the powdered sugar to "flour" the dough roll to prevent it from sticking to your counter top or candy prep board.
Mix remainder of sugar, butter, and vanilla in a large bowl. Add milk in the smallest of increments, a few drops at a time. Be very careful to not use more milk than needed in order to mix these ingredients. This should resemble a dry loaf similar to bread dough. If too much milk is used, the mixture cannot be rolled out.
When ingredients are thoroughly mixed, sprinkle the reserved powdered sugar on your prep area. Use a rolling pin to roll the loaf into the shape of a flat pie crust, about 1/4-inch thick.
Once the dough has been rolled to resemble a flat crust, use a table knife to generously cover the flat dough with the peanut butter. Roll the dough into a log shape, similar to a miniature jelly roll.
Cut into small pieces, 1/3- to 1/2-inch thick. The final result will be pieces that look like pretty pinwheels.