Using electric beaters, beat butter with icing sugar, granulated sugar, vanilla and salt until light and fluffy. Mix in flour just until combined. Fold in cereal.
Divide dough in half and shape into 2 logs, about 7-½ inches long and 1-½ inches in diameter. Wrap each in plastic wrap; refrigerate for 1 hour or until firm.
Preheat over to 300 degrees F. Line 2 baking sheets with parchment paper. Cut each log into ¼ inch slices and place 1-inch apart on the prepared baking sheets.
Bake, in batches, for 15-20 minutes or until lightly golden on the bottom. Cool completely on a rack.
If desired, dip half of each cookie into melted chocolate. Place on parchment lined baking sheet and refrigerate for 20 minutes or until firm.
Store in airtight container for up to 1 week or freeze for up to 1 month.