When to add marshmallows to jello?

Marshmallows should be added to Jello during the cooling process, once the Jello has been mixed with boiling water and the powder has dissolved. Adding marshmallows too early can cause them to melt completely, losing their shape and texture. By adding them during the cooling process, the Jello will be at a lower temperature, allowing the marshmallows to partially melt and create a creamy, marshmallow-infused texture in the final dish.