1 cup boiling water
2 (6 ounce) boxes grape-flavored Jell-O® mix
1 cup Tennessee whiskey (such as Jack Daniels ®)
Arrange 12 2-ounce plastic cups on a baking sheet.
Slowly pour boiling water over gelatin mix in a bowl while whisking. Continue whisking while streaming whiskey into the gelatin mixture. Pour mixture into plastic cups.
Refrigerate until set, 8 hours to overnight.