3 quarts hot water
2 cups white sugar
1/2 cup instant coffee crystals
2 quarts milk
1 (16 ounce) can chocolate syrup (such as Hershey’s®)
1 tablespoon vanilla extract
1 gallon vanilla ice cream
Stir hot water, sugar, and instant coffee together in a bowl until sugar and coffee are dissolved. Add milk, chocolate syrup, and vanilla extract; mix well. Chill in refrigerator, 8 hours to overnight. Stir ice cream into punch before serving.