Caramel Toffee Crunch Cake Recipe

I finally perfected my Caramel Toffee Crunch Cake, with tender, moist layers studded with crunchy toffee pieces and finished with a glossy caramel sauce that required several iterations to nail.

I still get a little thrill when I slice into my Caramel Toffee Crunch Cake. The tender layers give way to pockets of crisp texture, and the top crunch makes people stop talking and just stare.

I love how a simple hit of unsalted butter brings depth to the whole thing, and those toffee bits scattered through the batter? Pure chaos in the best way.

I wont lie, its a showstopper that feels fancy but is totally doable. Bring it to your next get together and watch jaws drop, its exactly the kind of thing I call Desserts That Wow

Ingredients

• All purpose flour: Mostly carbohydrates and some protein, gives structure but little fiber.
• Unsalted butter: Rich in saturated fat and calories, adds creaminess and tender crumb.
• Granulated sugar: Pure carbs, boosts sweetness and browning, no real nutrients.
• Light brown sugar: Same sugary carbs but molasses gives moisture and slight caramel flavor.
• Eggs: High quality protein, moisture and lift, helps bind ingredients together.
• Milk and sour cream: Adds fat, calcium and tang, keeps cake moist and tender.
• Caramel sauce: Concentrated sugar and butter, very sweet and rich, adds sticky depth.
• Toffee bits: Crunchy bits of sugar and butter, give texture and intense sweetness.
• Pecans or walnuts: Provide healthy fats, fiber and some protein, add toasted crunch.
• Confectioners sugar: Powdered sugar makes silky frosting, pure carbs, adjust sweetness easily.

Ingredient Quantities

• 3 cups all purpose flour, spooned and leveled
• 1 tablespoon baking powder
• 1/2 teaspoon baking soda
• 1 teaspoon fine salt
• 1 cup (2 sticks) unsalted butter, softened
• 1 1/2 cups granulated sugar
• 1/2 cup packed light brown sugar
• 4 large eggs room temp
• 1 cup whole milk room temp
• 1/2 cup sour cream room temp
• 2 teaspoons vanilla extract
• 1 1/4 cups granulated sugar for caramel
• 6 tablespoons unsalted butter for caramel, cut into pieces
• 3/4 cup heavy cream for caramel, warmed
• 1 teaspoon vanilla extract for caramel
• 1/2 teaspoon sea salt or kosher salt for caramel
• 1 1/2 cups toffee bits (Heath or Skor) or chopped toffee bars
• 1 cup chopped toasted pecans or walnuts, optional
• 1 1/2 cups unsalted butter softened for caramel buttercream
• 4 cups confectioners sugar sifted
• 1/2 cup caramel sauce (reserve from caramel above), more if needed
• 2 to 3 tablespoons heavy cream or milk for buttercream
• 1 teaspoon vanilla extract for buttercream
• Flaky sea salt for finishing, optional
• Extra toffee bits for sprinkling, about 1/2 cup

How to Make this

1. Preheat oven to 350F and grease and line two 9 inch round pans with parchment; whisk together 3 cups all purpose flour, 1 tablespoon baking powder, 1/2 teaspoon baking soda and 1 teaspoon fine salt and set aside.

2. In a large bowl cream 1 cup (2 sticks) softened unsalted butter with 1 1/2 cups granulated sugar and 1/2 cup packed light brown sugar until light and fluffy, about 3 to 4 minutes; add 4 large room temp eggs one at a time, beating after each, then stir in 2 teaspoons vanilla.

3. Mix 1 cup whole milk and 1/2 cup sour cream together; add the dry ingredients to the butter mixture in three additions, alternating with the milk mixture, beginning and ending with flour, just until combined; don’t overmix or the cake will be tough.

4. Toss 1 1/2 cups toffee bits (and the optional 1 cup chopped toasted pecans or walnuts if using) with a tablespoon of flour so they don’t sink, fold them into the batter gently, divide batter between pans and smooth tops.

5. Bake 25 to 30 minutes, rotating pans halfway, until a toothpick comes out with a few moist crumbs; cool in pans 10 minutes then turn out to wire racks to cool completely.

6. While cakes bake, make the caramel: heat 1 1/4 cups granulated sugar in a heavy bottomed saucepan over medium heat, swirling occasionally until it melts and turns a deep amber, be careful it can go from perfect to burnt fast; remove from heat and whisk in 6 tablespoons unsalted butter (cut into pieces) until melted, then slowly whisk in 3/4 cup warmed heavy cream (it will bubble), stir in 1 teaspoon vanilla and 1/2 teaspoon salt. Let caramel cool to room temp, then reserve 1/2 cup for the buttercream and keep the rest for drizzling.

7. Make the caramel buttercream: beat 1 1/2 cups softened unsalted butter until creamy, add 4 cups sifted confectioners sugar a cup at a time on low, then add the reserved 1/2 cup caramel, 1 teaspoon vanilla and 2 to 3 tablespoons heavy cream or milk to reach spreadable consistency; beat on medium until light and fluffy, taste and add a bit more caramel if you want it stronger.

8. Level the cooled cakes, place one layer on your cake plate, spread a thin layer of buttercream, scatter a few extra toffee bits and some toasted nuts, drizzle a little of the cooled caramel sauce, then top with second cake layer.

9. Do a thin crumb coat of buttercream over the whole cake and chill 15 to 20 minutes, then finish frosting smoothly. Press the extra 1/2 cup toffee bits around the top or edge as desired, drizzle more caramel on top, and sprinkle flaky sea salt for contrast if you like.

10. Chill briefly to set the frosting, then bring to room temp before serving so the caramel is gooey; store covered in the fridge up to 3 days, bring back to room temp before serving.

Equipment Needed

1. Two 9 inch round cake pans, greased and lined with parchment paper
2. Stand mixer or electric hand mixer (for creaming butter and whipping the buttercream)
3. Mixing bowls (one large for batter, one medium for dry ingredients or milk mix)
4. Measuring cups and spoons (and a kitchen scale if you like precision)
5. Rubber/silicone spatula and a whisk for folding and scraping the bowl
6. Heavy bottomed saucepan plus a heatproof whisk or wooden spoon for the caramel
7. Wire cooling rack and a baking sheet (for toasting nuts or catching drips)
8. Serrated knife or cake leveler and an offset spatula for frosting smooth tops
9. Toothpicks for doneness testing and oven mitts for safety

FAQ

Caramel Toffee Crunch Cake Recipe Substitutions and Variations

• All purpose flour (3 cups): swap for cake flour for a softer, lighter crumb (use same volume), or use a 1-to-1 gluten free baking blend plus 1/2 tsp xanthan gum if your blend needs it. Whole wheat pastry flour works too for a nuttier flavor, you’ll get a slightly denser cake though.
• Unsalted butter in the cake (1 cup): replace with neutral oil like canola or vegetable oil for a moister crumb, use 3/4 cup oil for every 1 cup butter. Or use stick margarine or plant based butter 1-to-1, but flavor will be milder.
• Milk (1 cup) + Sour cream (1/2 cup): combine them into 1 1/2 cups buttermilk for a tangy, tender cake, or use 1 cup milk plus 1/2 cup plain yogurt thinned with a little water if needed. Both keep the acidity for the leaveners to work right.
• Heavy cream for caramel (3/4 cup): swap with warmed evaporated milk for a lighter caramel, or use half and half for a bit less richness. Full fat coconut milk can be used if you’re dairy free, but expect a noticeable coconut flavor.

Pro Tips

– Make sure your butter, eggs, milk and sour cream are really room temp, not kinda warm, not straight from the fridge. They blend smoother, trap air better and your cake will be lighter. If something is still cold, pop it in a warm spot for 15 to 30 minutes.

– When you’re making the caramel, watch it like a hawk and swirl the pan instead of stirring too much. Pull it off heat at a deep amber, then add the butter off the burner and drizzle in the warm cream slowly or it will sputter. If a few sugar crystals form on the side use a wet pastry brush to wash them down, that usually saves it.

– Prevent toffee from sinking by tossing the bits with a little flour and folding them in gently, and use slightly larger bits on top instead of mixing all in the batter. Also try stirring only until combined, overmixing will make the toffee sink and the cake tough.

– For the buttercream, start adding the reserved caramel a little at a time and taste as you go, you can always add more. If the frosting gets too soft chill for 10 to 15 minutes and re-whip, if its too stiff add a teaspoon of warm cream at a time. Chill the cake briefly after the crumb coat so the final layer goes on clean, then bring the whole cake to room temp before serving so the caramel is gooey.