Seafoam Candy

Seafoam Candy

The Spruce / Kristina Vanni

Prep: 10 mins
Cook: 20 mins
Total: 30 mins
Servings: 12 servings
Nutrition Facts (per serving)
136 Calories
0g Fat
36g Carbs
0g Protein
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Nutrition Facts
Servings: 12
Amount per serving
Calories 136
% Daily Value*
Total Fat 0g 0%
Saturated Fat 0g 0%
Cholesterol 0mg 0%
Sodium 361mg 16%
Total Carbohydrate 36g 13%
Dietary Fiber 0g 0%
Total Sugars 36g
Protein 0g
Vitamin C 0mg 0%
Calcium 18mg 1%
Iron 0mg 1%
Potassium 32mg 1%
*The % Daily Value (DV) tells you how much a nutrient in a food serving contributes to a daily diet. 2,000 calories a day is used for general nutrition advice.
(Nutrition information is calculated using an ingredient database and should be considered an estimate.)

Seafoam candy is a vintage treat that gets its name from its signature airy and bubbly appearance. This confection goes by several other names as well, depending on your region. Some call it sponge candy, honeycomb, hokey pokey, fairy food, or cinder toffee. This sweet treat is not only filled with flavor from the caramelized sugars, but it provides plenty of texture and interest from the air bubbles created when baking soda combines with vinegar. This recipe uses brown sugar and dark corn syrup for an enhanced molasses flavor, but granulated sugar and light corn syrup can also be used.

If you've ever done the classic science experiment with baking soda and vinegar, you know that the combination creates an incredibly bubbly "volcano" when the two ingredients combine. This recipe uses the same chemical reaction with the sweet addition of caramelized sugar. The key is to work quickly once the baking soda is added and not to disturb the candy as it pours out of the pan or as it sits, to make sure all the beautiful bubbles remain.

Seafoam candy can be enjoyed on its own or dipped in chocolate. It is also wonderful when crushed and sprinkled on top of ice cream or cakes, or just eaten out of hand.


  • 1 cup brown sugar, firmly packed

  • 1 cup dark corn syrup

  • 1 tablespoon white vinegar

  • 1 tablespoon baking soda

Steps to Make It

  1. Gather the ingredients.

    Seafoam candy ingredients
    The Spruce / Kristina Vanni
  2. Line a 9 x 13-inch baking pan with nonstick foil. Generously grease the foil with cooking spray. Set aside. 

    Pan lined with foil and greased
    The Spruce / Kristina Vanni
  3. Use an extra-large heavy saucepan. When the candy foams, it grows significantly in size and needs extra space. (Be on the safe side and use a pan that is larger than you anticipate.)

    Combine the brown sugar, dark corn syrup, and vinegar over medium heat. Stir constantly until the sugar is dissolved and the mixture comes to a boil.

    Combine the brown sugar, dark corn syrup, and vinegar
    The Spruce / Kristina Vanni
  4. Once the mixture is boiling, cook without stirring until a candy thermometer reaches 300 F or "hard-crack" stage.

    Candy thermometer in a saucepan
    The Spruce / Kristina Vanni
  5. Remove the saucepan from the heat and add the baking soda, stirring rapidly.

    Boiling sugar in a pan
    The Spruce / Kristina Vanni
  6. The mixture will quickly puff up and begin to foam. Keep stirring just until all of the baking soda has been combined. Work quickly. 

    Sponge candy forming in the pan
    The Spruce / Kristina Vanni
  7. Immediately pour into the prepared pan. Do not spread the candy, it will naturally spread out on its own in the pan. Do not scrape the mixture from the saucepan, simply allow the candy to pour naturally out of the pan. Some will remain in the pan, but that's OK. Even scraping those last bits from the pan will cause the candy to deflate and fall.

    Allow the candy to cool completely, undisturbed. At this point, if you touch the candy at all, it will pop the air bubbles that give this candy its signature look and texture. 

    Seafoam candy cooling in the pan
    The Spruce / Kristina Vanni
  8. Once the candy is cool and set, lift the foil out of the pan. Peel back the foil and break the candy into pieces. 

    Seafoam candy broken into pieces
    The Spruce / Kristina Vanni
  9. Store seafoam candy in jars or an airtight container, and store at room temperature. Any exposure to moisture will soften the candy.

    Seafoam candy in a container
    The Spruce / Kristina Vanni