Wash the green grapes thoroughly.
Drain them well using a colander.
Pat the grapes completely dry using a clean kitchen towel.
Place the grapes into a large mixing bowl.
Drizzle the chamoy evenly over the grapes.
Gently toss until every grape is lightly coated.
Sprinkle the Tajin seasoning over the grapes.
Toss again until the seasoning is evenly distributed.
Line a baking sheet or tray with parchment paper.
Spread the grapes into a single layer.
Freeze for 2 to 3 hours until firm.
Before serving, allow the Frozen Green Grapes with Tajin to rest for 3 to 4 minutes so they're easier to bite into and gentler on your teeth.