Peanut Butter Fudge Brittle Cake
Prep time
Bake time
Total time
As with any building on recipes project it is best to make a couple recipes in advance.
The classic fudge filling and aquafaba buttercream is a great way to save time by making it a day or two ahead
I am using Earth Balance vegan butter which is quite salty in my opinion, so I omit the salt in the cake recipe. You may add ½ teaspoon if you are using a less salty vegan butter
Serves: 1-7" cake
  • 1 RecipeAquafaba Swiss Buttercream
  • 1 cup Peanut Butter add to the butter cream at the last stage of mixing
  • ½ Recipe Fudge Icing
  • [b]For the Cake:
  • Vegan Butter 1 cup + 2 tablespoons (255g)
  • Granulated Sugar 2¼ cup (450g)
  • Creamy Peanut Butter 1 cup (240g)
  • Flax Meal 5 Tablespoon (40g)
  • Warm Water ¾ cup (180ml)
  • Vanilla Extract 3 teaspoon (15ml)
  • Soy Milk ¾ cup (180ml)
  • Vinegar 1 Tablespoon (15ml)
  • All Purpose Flour 2½ cups (312g)
  • Baking Powder 1¼ teaspoons
  • For the Peanut Butter Fudge:
  • Peanut Butter 1 cup (240g)
  • Corn Syrup or Agave 1½ cup
  • Coconut Oil or Vegan Butter ¼ cup (56g)
  • Vanilla Extract 2 teaspoon (10ml)
  • For the Peanut Brittle:
  • Sugar 1 cup (200g)
  • Corn Syrup ½ cup (120ml)
  • Water ¼ cup (60ml)
  • Vegan Butter 2 Tablespoons (28g)
  • Baking Soda 1 teaspoon
  • Unsalted Raw Peanuts 1 cup (150g)
  • For the Ganache Drizzle:[/b]
  • Semi Sweet Chocolate 4 ounces
  • Soy or Almond Milk ¼ cup (60ml)
  • For the Peanut Butter Fudge:
  • Creamy Peanut Butter 1 cup
  • Agave Syrup ½ cup
  • Coconut Oil ½ cup
  • Vanilla Extract 1 teaspoon (5ml)
  1. Prepare the buttercream as listed on the blog post for that recipe and add the peanut butter at the last stage of mixing.
  2. Prepare the fudge icing as well and reserve until needed
  3. Prepare the ganache about an hour before you are ready to assemble the entire cake, or make ahead and rewarm when needed
  4. For the Cake:
  5. Preheat the oven to 350°F and grease and parchment paper 4-7" cake pans or 2-8" cake pans
  6. Sift the flour with the baking powder
  7. Combine the flax meal with the warm water and set aside to thicken about 5 minutes.
  8. Add the vinegar to the soy milk
  9. Cream the vegan butter with the sugar on medium to high speed until fluffy about 3 minutes.
  10. Add the peanut butter and mix well
  11. Add the vanilla extract
  12. Add the flax paste and cream well to combine
  13. Next add about ⅓ of the flour mixture and mix just until it is incorporated
  14. Then add about half of the soy milk mixture, mix to combine
  15. add another ⅓ of the flour and then the rest of the milk mixture
  16. Ending with the last addition of flour.
  17. Divide evenly between the prepared pans and bake for approximately 28-30 minutes or when they are springy to the tough when you gently press the centers
  18. For the Peanut Butter Fudge:
  19. Combine the peanut butter and agave or corn syrup in a heavy bottom sauce pot and bring to a boil stirring constantly.
  20. Boil for about 1 minute then add the coconut oil and vanilla extract and transfer to a bowl to cool
  21. For the Peanut Brittle:
  22. Combine the sugar, cornsyrup and water in a heavy sauce pot and bring to a boil.
  23. Once it boils, Insert a candy thermometer and continue to boil without stirring until it is 300-309°F (*See note above) it should just start to turn golden brown, then add the vegan butter, baking soda, vanilla extract and peanuts.
  24. Stir well to combine
  25. Spread mixture on a lightly oiled sheet pan and let cool
  26. Assemble cake as shown in the video
This cake can be stored at room temperature for up to 3 days in a cool spot or for longer storage refrigerate in an airtight container for up to 1 week.

Best served room temperature
Recipe by Gretchen's Vegan Bakery at