I ruined my first three batches of peanut butter fudge. They were grainy, sugary messes that crumbled like sand. The problem? I was following the same vague advice everyone else gives. It wasn't until I started treating fudge like the precise chemical reaction it is that I cracked the code. The secret weapon isn't just peanut butter—it's that jar of marshmallow creme sitting on your shelf. This recipe, honed over a decade of holiday disasters and triumphs, delivers a fudge that's impossibly smooth, creamy, and foolproof.

What's Inside This Guide

Why Marshmallow Creme is the Non-Negotiable Game-Changer

Let's clear something up right away. This isn't just about sweetness. Marshmallow creme (like the classic Fluff brand) is a stabilizer. Its structure is a foam of egg whites and corn syrup that's already been cooked. When you add it to the hot sugar and peanut butter mixture, it does two critical things.peanut butter fudge recipe

First, it interferes with sugar crystallization. That's the science-y term for the grains that ruin traditional fudge. The proteins and structure in the creme get in the way of sugar molecules lining up into big, crunchy crystals. Second, it introduces air and helps emulsify the fats from the peanut butter with the sugar syrup. The result? A texture that's consistently smooth, almost melt-in-your-mouth, with a body that holds its shape without being rock hard.

The Big Mistake I See: People try to substitute regular marshmallows. Don't. They melt unevenly, often leave chewy bits, and don't provide the same pre-stabilized structure. It's the difference between using pre-made whipped cream and trying to whip your own cream in the middle of the fudge process—too many variables.

Your Ingredient Breakdown: What Really Matters

You can find a list of ingredients anywhere. Here's what each one actually does, and where you can (and can't) cut corners.marshmallow creme fudge

Ingredient Quantity Its Real Job & Pro Notes
Granulated Sugar 2 cups Provides the base structure and sweetness. Don't swap for brown sugar here—the molasses adds moisture and changes the crystallization game completely.
Evaporated Milk (Not sweetened condensed!) 5/8 cup (3/4 cup less 2 tbsp) This is key. It's concentrated milk with less water, so you can cook the syrup to the right temp without curdling. Using regular milk adds too much water, extending cooking time and risking scorching.
Butter 1/2 cup (1 stick) Adds richness, smooth mouthfeel, and helps control crystallization. Use unsalted so you control the salt. Salted butter can work, but reduce added salt by 1/4 tsp.
Marshmallow Creme (like Fluff) 1 jar (7 oz) The MVP. Provides stability, smooth texture, and prevents graininess. Spoon it lightly into the measuring cup; don't pack it.
Peanut Butter 1 cup Use a standard, no-stir creamy peanut butter like Jif or Skippy. The natural, oily kind will separate and make your fudge greasy. The stabilizers in commercial brands are your friend here.
Vanilla Extract 1 tsp Flavor enhancer. Add it after cooking, with the peanut butter.
Salt 1/4 tsp Makes the sweet and peanut flavors pop. Non-negotiable.

The Step-by-Step Process (Where Most Go Wrong)

This is where you win or lose. Read this twice before you turn on the stove.easy peanut butter fudge

Phase 1: The Sugar Syrup Foundation

Grab a heavy-bottomed, 3-quart saucepan. Light bottoms scorch. Combine the sugar, evaporated milk, and butter. Here's the first critical step: dissolve, don't boil.

Turn the heat to medium-low. Stir constantly with a wooden spoon or silicone spatula until the butter melts and the sugar is completely dissolved. How do you know? Dip your fingers in cold water, then carefully grab a drop of the mixture and rub it between your fingers. If you feel any grit, keep stirring. No grit? Stop stirring. Place your candy thermometer in the pot.

Bring the mixture to a full, rolling boil over medium heat. Do not stir. If sugar crystals form on the sides of the pot, use a wet pastry brush to wash them down. Boil until the thermometer reads 234°F to 240°F (112°C to 116°C). This is the soft-ball stage. A 2-3 degree under-shoot gives softer fudge; an over-shoot gives harder fudge. I aim for 236°F for perfect texture.

Phase 2: The Magic Mix-In

Remove the pot from heat immediately. Take out the thermometer. Quickly add the marshmallow creme, peanut butter, vanilla, and salt. Don't dawdle—the residual heat is doing the work.

Now, beat it. Use a sturdy spoon or a hand mixer on low. Beat until everything is just combined and the marshmallow creme is fully melted. This takes about 1-2 minutes. Stop as soon as it's smooth. Over-beating at this stage can actually encourage graininess by agitating the sugar.peanut butter fudge recipe

Phase 3: Setting Up for Success

Pour the fudge immediately into a prepared 8x8 or 9x9 inch pan lined with parchment paper (let the paper hang over the sides for easy removal). Smooth the top with a spatula.

Let it cool at room temperature until set. This takes 2-4 hours. Do not refrigerate to speed it up! Refrigeration causes moisture condensation and can lead to a sticky surface or sugar bloom (those white spots).

Expert Tips & Troubleshooting

  • The Tool You Must Have: A digital candy thermometer. Clip it to the side of the pot, ensuring the tip isn't touching the bottom. Test its accuracy by seeing if it reads 212°F in boiling water. If it's off, adjust your target temp accordingly.
  • Weather Matters: On a humid, rainy day, your fudge might take longer to set and can stay slightly softer. It's fine, just be patient. The sugar is absorbing ambient moisture.
  • Cutting Clean Squares: Use a large, sharp chef's knife. Run it under very hot water, wipe it dry, and make a cut. Wipe the blade clean and re-heat it for each cut. This gives you those perfect, clean edges you see in bakeries.
  • Storage: Store in an airtight container at room temperature with parchment between layers for up to 2 weeks. It freezes beautifully for 3 months. Thaw in the container overnight.marshmallow creme fudge

Your Fudge Questions, Answered

Why does my peanut butter fudge with marshmallow creme turn out grainy or sugary?
Graininess is the #1 fudge failure, and it almost always comes down to sugar crystallization. The most common culprit is not dissolving the sugar completely before it boils. Stir the sugar and milk mixture over medium-low heat until you can't feel any sugar granules when you rub the mixture between your fingers. Then, and only then, stop stirring and bring it to a boil. Another sneaky cause is scraping the sugary residue from the sides of the pot back into the boiling syrup. Use a wet pastry brush to wash down the sides instead.
Can I use marshmallows instead of marshmallow creme in this fudge recipe?
Technically you can, but I strongly advise against it for the classic creamy texture. Marshmallow creme (like Fluff) is a smooth, stabilized foam that integrates seamlessly, acting as an emulsifier. Chopped marshmallows melt unevenly, can create chewy pockets, and don't provide the same structural guarantee. If you must substitute, use a 7-ounce jar of marshmallow creme for every 10 ounces of regular marshmallows, and melt them very slowly with the peanut butter, expecting a slightly different, less foolproof result.easy peanut butter fudge
How do I store peanut butter fudge with marshmallow creme to keep it fresh?
Store it in an airtight container at room temperature, layered between sheets of parchment or wax paper, for up to 2 weeks. Do not refrigerate it. Refrigeration causes the fudge to dry out, become hard, and can promote sugar bloom (those white, dusty spots). For longer storage, up to 3 months, wrap individual pieces tightly in plastic wrap, then place in a freezer bag. Thaw overnight at room temperature in its wrapping to prevent condensation.
My fudge is too soft and won't set. What went wrong and can I fix it?
A soft, unset fudge usually indicates the sugar syrup didn't reach the proper temperature (the soft-ball stage, 234-240°F / 112-116°C). A candy thermometer is non-negotiable for consistency. If it's still soft after cooling, you have a few salvage options. For a slightly soft batch, chilling it in the fridge will firm it up, though the texture won't be perfect. For a major fail, you can re-melt it. Add 1-2 tablespoons of milk, reheat slowly to 234°F, and beat again. The texture will be grainier, but it will set.

There you have it. It's not magic, it's just understanding the rules of the game. With this peanut butter fudge with marshmallow creme recipe, you're not just following instructions; you're learning the *why* behind each step. That's what turns a recipe into a reliable skill. Now go make a batch that'll make everyone think you bought it from some fancy confectionery. I won't tell.