Homemade marshmallows are made from four basic ingredients — gelatin, sugar, corn syrup, and flavoring — whipped into a soft, pillowy slab that you cut into squares. The honest reason to make them is texture: they are noticeably softer and more tender than anything from a bag. Using a whole vanilla bean plus extract gives you both depth and those familiar black specks throughout every piece.
Before you start
The two things that actually determine whether this recipe works are temperature and timing. Your sugar syrup must reach exactly 240°F — not close, not roughly. Below that and the marshmallows won’t set firmly enough to cut cleanly; above it and they turn dense. A reliable candy thermometer is non-negotiable here. The second thing: once you start pouring the hot syrup into the bloomed gelatin, you need to whip continuously and not stop until the mixture is thick, glossy, and has cooled to lukewarm — that full 10 to 12 minutes is doing real structural work, not just mixing. Shortcut it and you’ll get a flat, sticky slab instead of a fluffy one. A hand mixer works fine for this; just keep the bowl steady.
Troubleshooting
- Marshmallow won’t release from the pan: You didn’t use enough of the powdered sugar and cornstarch mixture on the bottom and sides. Next time, be generous — it should look well-coated, not lightly dusted. To rescue a stuck slab, run a thin offset spatula around all four edges before attempting to flip it.
- Grainy or crystallized texture: Sugar crystals formed on the sides of the saucepan and got stirred back in. Keep a pastry brush dipped in water nearby and brush down the sides of the pan while the syrup heats, before it reaches a boil.
- Marshmallow is sticky even after setting overnight: Humidity is usually the culprit. Marshmallows absorb moisture from the air. If your kitchen is humid, toss the cut pieces more thoroughly in the cornstarch-powdered sugar mix and store them in an airtight container with a small piece of parchment between layers.
- Vanilla bean seeds clumped together instead of distributing evenly: Add them a few seconds before the extract and let the mixer disperse them before adding the liquid. Rubbing the scraped seeds between your fingers before adding them also helps break up any clumps.
- Flat, dense result after cutting: The mixture was either under-whipped or the syrup was poured in too fast. Pour in a slow, steady stream down the side of the bowl — not directly onto the beaters — and don’t rush the whipping time. Skip the garnish of extra vanilla bean on top; it doesn’t add flavor and just makes cutting messier.
Keeping it fresh
Store cut marshmallows in an airtight container at room temperature for up to 3 weeks — keep them away from heat and moisture, and separate layers with parchment. Do not refrigerate them; the fridge introduces humidity and makes them sticky and dense. If you want to work ahead, you can make the full slab and leave it uncut in the pan, loosely covered, for up to 24 hours before slicing. Marshmallows can be frozen: place cut pieces in a single layer on a parchment-lined tray, freeze until solid (about 2 hours), then transfer to a zip-lock bag for up to 2 months. Thaw at room temperature for 20 to 30 minutes and toss in a fresh coating of the cornstarch-powdered sugar mix before serving.
Vanilla Bean Marshmallows
Equipment
- Stand Mixer
- Medium saucepan
- Candy Thermometer
- 8x8-inch baking dish
- Parchment Paper
- Sifter or fine-mesh sieve
Ingredients
- 3 envelopes unflavored gelatin
- ½ cup cold water divided
- 2 cups granulated sugar
- ⅔ cup light corn syrup
- ¼ teaspoon Kosher salt
- 1 whole vanilla bean seeds scraped
- 1 tablespoon vanilla extract
- ¼ cup powdered sugar for dusting
- ¼ cup cornstarch for dusting
Instructions
- Prepare the Gelatin Mixture: In the bowl of a stand mixer, combine 1/2 cup cold water and unflavored gelatin. Let it sit for about 10 minutes to bloom while you prepare the sugar syrup.
- Make the Sugar Syrup: In a medium saucepan, combine granulated sugar, 1/4 cup cold water, light corn syrup, and kosher salt. Place over medium-high heat, attach a candy thermometer, and stir constantly until the sugar dissolves. Let the mixture boil until it reaches 240°F (116°C), without stirring, about 8-10 minutes.
- Combine and Whip: With the mixer on low speed, carefully pour the hot sugar syrup into the gelatin mixture down the side of the bowl. Gradually increase the mixer speed to high and whip until the mixture is thick, fluffy, and lukewarm, about 10-12 minutes. Add vanilla bean seeds and vanilla extract during the last minute.
- Prepare the Pan: While the marshmallow mixture is whipping, line an 8x8-inch baking dish with parchment paper and lightly spray with nonstick spray. In a small bowl, sift together powdered sugar and cornstarch, then generously dust the pan.
- Pour and Set: Using a spatula, spread the mixture evenly in the prepared pan. Dust the top with the sugar-cornstarch mixture. Let it set for at least 4 hours or overnight, uncovered, at room temperature.
- Cut and Coat: Turn the set marshmallow slab out onto a cutting board and peel off the parchment. Using a sharp knife dusted with cornstarch mixture, cut into squares. Toss pieces in extra powdered sugar-cornstarch mixture to prevent sticking.
Notes
- For a variation, replace vanilla bean with 1 teaspoon almond extract for almond-flavored marshmallows.
Nutrition
FAQ
Can I use powdered gelatin from a jar instead of the individual envelopes?
Yes — 3 envelopes equals about 2 and a quarter teaspoons each, so measure out 6 and three-quarter teaspoons total from a bulk jar. Bloom it in the same half cup of cold water for the same 10 minutes before you start the syrup.
Do I really need corn syrup, or can I substitute something else?
Corn syrup is doing a specific job here: it prevents the sugar from crystallizing as it cooks, which keeps the final texture smooth. Substituting honey or maple syrup changes the flavor noticeably and can affect how the syrup behaves at temperature, so stick with light corn syrup for a reliable result.
My vanilla bean is dried out and hard — can I still use it?
A very dry pod is difficult to split and won’t yield many seeds, so it’s better to skip it and use an extra half teaspoon of good vanilla extract instead. If the pod is just slightly firm, warm it briefly between your palms for 30 seconds before splitting — it softens enough to scrape.
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