An easy 3-ingredient Marshmallow Slime Recipe with an edible version for a fun sensory play activity with young kids.
What’s marshmallow slime?
Marshmallow slime is a fun, soft, stretchy dough for kids’ sensory play activities. It’s mainly made of melted marshmallows and a few other ingredients.
How to make marshmallow slime?
It is super easy to make a fun edible marshmallow slime at home. The ingredients you need are:
- Jumbo marshmallows – or mini marshmallows, simply weigh the amount for precision.
- Cooking oil – canola oil or sunflower oil, or coconut oil works well.
- Cornstarch or powdered sweetener –
Disclaimer: Cornstarch is not toxic, but it’s still not to be taken in large amounts! This slime won’t hurt your little ones if they put some in their mouth, but don’t turn it into a full-on breakfast!
First, place the jumbo marshmallows into a large microwave-safe mixing bowl. Place the bowl in the center of the microwave and microwave on high power 900W for 30 seconds until the marshmallows puff up and double in size.
Stir in oil
The melted marshmallow mixture is very hot, so wear gloves to remove the bowl from the microwave. Then, stir in vegetable oil. It won’t dissolve well in the mixture, but it helps unstick the marshmallow mixture from the bowl. If you want to color your slime, stir in a few drops of food coloring now.
Stir in cornstarch and play!
Now, add corn starch, one tablespoon at a time, until your slime gets firmer, less sticky, and easy to handle by hand.
How to store marshmallow slime?
Unfortunately, marshmallow slime doesn’t store very well. It hardens with time, even if you store it in a sealed container.
How to soften marshmallow slime?
The lifespan of marshmallow slime is very short. Usually, after 20 minutes, the texture turns hard, and it’s not fun to play with it.
This is a natural chemical reaction. The more you play, stretch, or knead the slime, the fewer water molecules are left in the marshmallow, and it hardens.
A great way to soften marshmallow slime is to bring it back to the microwave-safe bowl and microwave for 10 seconds. Then, stir with a spoon and add more corn starch if it becomes sticky. Finally, play by hand when it cools down.
Is marshmallow slime edible?
Many marshmallow slime recipes use corn starch as the main ingredient simply because it’s the best to achieve a non-sticky, stretchy marshmallow slime.
However, it’s not safe to eat raw cornstarch for many reasons. It can carry harmful bacteria and if eaten in large amounts. It can generate diseases like anemia. If you want to make edible slime, use only ingredients that are safe to be eaten raw. It means replacing cornstarch with powdered sugar.
How to make edible slime with marshmallows?
To make edible slime with marshmallows, replace corn starch with powdered sugar. You can’t eat raw corn starch, but raw powdered sugar is safe.
However, this simple swap impacts the slime texture. The texture of edible marshmallow slime made with powdered sugar is stickier, and you may have to add more powdered sugar to reach a firmer texture.
This option will be a high-sugar slime, so even if it’s edible, don’t let your child eat a lot of it! Sugar is addictive, bad for your kids’ teeth and growth.
How to clean your fingers from sticky marshmallow slime?
The best way to unstick marshmallow slime from hands, surfaces, or clothes is with hot water. Marshmallow slime is pure sugar, so it dissolves very well with water. Rub your hands under lukewarm water, and the slime is going to melt and disappear.
You can add many sensory things to this slime recipe to engage more senses.
For example, try adding 1/2 cup of:
- Colored sequins – pick some that match the season, like Halloween, Easter, or Christmas shape sequins.
- Crumbled biscuits – if you make the edible version, add crumbled Oreo to make a cookie and cream slime.
Marshmallow Slime Recipe
- 2 oz Marshmallow
- 1 tablespoon Vegetable Oil canola oil or sunflower oil
- 3 tablespoons Corn Starch replace with powdered sugar for an edible version
- Before you start, remember that it's not safe to eat raw cornstarch as it can create bloating or carry bacteria. For an edible version, use powdered sugar instead, keeping in mind that the texture will be way stickier.
- In a medium-sized microwave-safe mixing bowl, add marshmallows. Place the bowl in the center of the microwave and microwave for 30 seconds until the marshmallow puffs up.
- Watch out the mixture is very hot, so use gloves to remove the bowl from the microwave.
- Add vegetable oil to the bowl and stir the mixture with a spoon. It will not dissolve well and stay glossy and oily, so start adding cornstarch, 1 tablespoon at a time. The slime is forming as you stir more cornstarch. Adjust the amount of corn starch, adding more to make the slime less sticky and firmer. Use your hands only when the mixture reaches a safe temperature.
- Marshmallow slime hardens quickly as the water molecules evaporate while playing with it. You can soften the slime by bringing it back to the microwave-safe bowl and microwave for 10 seconds. Always stir with a spoon at first to avoid burning yourself. Then when it's safe to touch, knead and play and adjust the texture by adding a pinch more cornstarch to dry it out or drops of oil if too sticky.
- Marshmallow slime doesn't store well and must be discarded after use.
- If the slime sticks too much to your fingers, rub your hand with water, not with some oil! Simply clean surfaces and bowl with hot water. The slime will melt and clean easily.