Jul 14 2026
RestaurantsUnion AssemblyPeanut Butter Filling/ Toffee Crunch Recipe

Peanut Butter Filling/ Toffee Crunch Recipe

Inspired by Union Assembly
Time1h
Serves12

Make Peanut Butter Filling/ Toffee Crunch Recipe in just 1h . Get the full recipe with step-by-step instructions at pekinthechef.com.

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Ingredients

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Peanut Butter Filling

Method

Peanut Butter Filling

  1. 1

    Prepare ingredients

    Measure and bring the softened butter and peanut butter to room temperature so they combine smoothly. Sift the powdered sugar to remove any lumps.

  2. 2

    In the bowl of a stand mixer fitted with the paddle attachment (or a large bowl with an electric hand mixer), beat the softened butter on medium speed for 30–45 seconds until slightly fluffy.

  3. 3

    Add the creamy peanut butter and beat on medium speed until fully incorporated and smooth, about 1 minute.

  4. 4

    With the mixer on low, add the powdered sugar in two additions, scraping down the bowl between additions. After sugar is incorporated, add the heavy cream, vanilla extract, and kosher salt.

  5. 5

    Increase to medium-high speed and beat for 30–60 seconds until light, spreadable, and homogenous. Taste and adjust texture: if too stiff, add 1 teaspoon heavy cream at a time; if too loose, add up to 2 tablespoons more powdered sugar.

  6. 6

    Transfer the peanut butter filling to a piping bag or airtight container. If not using immediately, refrigerate up to 3 days; bring to room temperature and re-whip briefly before using.

Toffee Crunch

  1. 7

    Prepare pan and ingredients

    Line a baking sheet (roughly 9x13-inch or similar) with parchment paper or a silicone mat. Arrange the chopped peanuts near your stove and have the baking soda, salt, and a heatproof bowl ready.

  2. 8

    In a medium heavy-bottomed saucepan, combine the unsalted butter, light brown sugar, granulated sugar, and light corn syrup. Stir gently to combine over medium-low heat.

  3. 9

    Bring the mixture to a simmer, stirring occasionally to dissolve sugar. Once simmering, stop stirring and clip a candy thermometer to the pan (or use an instant-read thermometer). Continue cooking until the mixture reaches 300°F (149°C), the hard-crack stage, about 6–10 minutes depending on heat. Watch carefully to avoid burning.

  4. 10

    When the mixture reaches 300°F (149°C), immediately remove the pan from heat and carefully whisk in the baking soda. The toffee will foam and lighten in color. Stir in the chopped roasted peanuts until evenly distributed.

  5. 11

    Quickly pour the foamy toffee onto the prepared baking sheet and spread into an even layer (about 1/8–1/4 inch thick) using a small offset spatula. Work quickly before it sets.

  6. 12

    Sprinkle the surface evenly with the sea salt. Allow the toffee to cool and harden at room temperature for at least 30–45 minutes until brittle.

  7. 13

    Once cooled, break the toffee into small shards or pulse lightly in a food processor for a finer crunch. For very fine crumbs, pulse 6–10 short pulses; for chunky pieces, break by hand.

  8. 14

    Store the toffee crunch in an airtight container at room temperature for up to 1 week, or layer between parchment if stacking.

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