If you like piña coladas, you'll know that rimming the glass with chili seasoning is a rebel's move. Feel free to revert to a classic maraschino cherry garnish.
Combine all ingredients, except garnish, in a quart-size zip-top bag. Seal bag and freeze overnight. To serve, massage the bag to break up mixture. If desired, rub the rim of a glass with a wedge of lime and dip in chile-lime seasoning to coat. Tip slushie into a glass. Add garnish and serve immediately.
Make a bigger batch in a gallon-size zip-top bag for serving at a party.