If you have sugar and gelatin at home, try this homemade marshmallow

Combine Syrup with Gelatin:
With the stand mixer on low speed and the whisk attachment, slowly pour the hot sugar syrup into the gelatin mixture.
Be careful as the syrup is very hot.
Whip the Marshmallow Mixture:
Once all the syrup is added, increase the mixer speed to high and whip until the mixture becomes thick and white, resembling marshmallow fluff. This usually takes about 10-15 minutes.
Add Vanilla:
While the mixture is whipping, add 1 teaspoon of vanilla extract and continue to beat until fully incorporated.
Transfer to Pan:
Grease a 9×13 inch baking dish and dust it with powdered sugar.
Pour the marshmallow mixture into the prepared pan and smooth the top with a spatula.
Set and Cut:
Let the marshmallows sit at room temperature for at least 4 hours, or overnight, until fully set.
Once set, use a knife or cookie cutters dusted with powdered sugar to cut the marshmallows into squares or desired shapes.
Enjoy!:
Dust the cut marshmallows with more powdered sugar to prevent sticking.
Store in an airtight container at room temperature for up to two weeks.