Line an 8x8" pan with parchment & set aside
In a small microwave safe bowl, combine white chocolate chips & sweetened condensed milk
Microwave on 50% power in 30 second intervals - stirring in-between each interval until chocolate is melted & smooth (should take about 60-90 seconds total)
Fold in about 1/4 cup of the rock candy sprinkles & the butter extract
Transfer to prepared pan & press flat
Sprinkle with remaining candy & refrigerate for at least 2 hours to set
Store in an airtight container in a cool, dark place for up to 3-4 days