Cake Mix Toffee Bars

The first time I made these bars was on a rainy Tuesday afternoon when I needed something sweet but had zero energy for a complicated recipe. I stared at that box of cake mix in my pantry for ten minutes before deciding to see what would happen if I just added butter and egg and called it a day. The smell that filled my kitchen made my teenage son actually pause his video game and wander downstairs to investigate.

I brought these to a neighborhood potluck last summer and watched my friend Sarah literally corner the pan to guard the last two pieces. She asked for the recipe three times that evening and looked genuinely shocked when I told her about the cake mix shortcut, as if I had somehow broken the rules of honest baking.

Ingredients

• 1 box yellow cake mix: I have tested various brands and they all work beautifully here, but avoid butter flavored mixes as they compete with the toffee notes
• 1/2 cup unsalted butter, melted: Use real butter, not margarine, as it creates that rich shortbread like texture that elevates these from simple to special
• 1 large egg: Room temperature egg will blend more smoothly into the dough, though honestly I have used cold eggs in a rush and nobody noticed the difference
• 1 cup semi sweet chocolate chips: The semi sweet provides just enough bitterness to balance the sweet toffee and buttery base without becoming overwhelming
• 1 cup toffee bits: I keep Heath bits in my pantry year round now because they add that perfect crunch and buttery caramel flavor throughout
• 1/2 cup chopped pecans: These are optional but I highly recommend them as they add a lovely nutty undertone that complements the toffee beautifully

Instructions

Prepare your oven and pan:

Preheat your oven to 350°F and either grease your 9x13 inch baking pan with butter or line it with parchment paper, which makes lifting the bars out so much easier later.

Make the dough:

Dump the cake mix into a large bowl, pour in your melted butter, crack in the egg, and stir until everything comes together into a soft dough that holds together when you pinch it.

Press it into the pan:

Using your hands or the back of a spoon, press the dough evenly across the bottom of your prepared pan, making sure it is the same thickness throughout so they bake evenly.

First bake:

Bake for 15 minutes until the base is just set but not browned, keeping a close eye on it during the last few minutes as every oven runs differently.

Add the chocolate:

Remove the pan from the oven and immediately scatter your chocolate chips evenly over the hot surface, letting them sit for two to three minutes until they are shiny and melted.

Spread the chocolate:

Gently spread the melted chocolate with a spatula, being careful not to mix it into the base layer, then sprinkle the toffee bits and pecans evenly over the top.

Final bake:

Return the pan to the oven for eight to ten minutes until the toffee bits get slightly bubbly and the edges turn a beautiful golden brown.

The hardest part:

Let the bars cool completely in the pan before cutting, which I know is torture when your kitchen smells like this, but cutting while warm makes a terrible mess.

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My mom now requests these for every family gathering instead of her famous seven layer bars, which feels like a significant shift in the dessert hierarchy. Last Christmas my niece actually helped me make them and declared she was going to open a bakery that sold nothing but these bars.

Making Them Your Own

I have found that white chocolate chips work surprisingly well with the toffee bits if you want something sweeter and less intense. A tiny pinch of flaky sea salt right after that final bake takes these from delicious to cannot stop eating them territory.

Storage and Sharing

These bars keep beautifully in an airtight container at room temperature for up to five days, though in my house they rarely survive past day two. I have also wrapped individual bars in plastic wrap and frozen them for those emergency dessert moments.

Serving Suggestions

These bars are fantastic on their own but become absolutely next level served slightly warm with a scoop of vanilla ice cream melting into the chocolate. I also like to crumble them over vanilla yogurt for an incredibly indulgent breakfast.

• Cutting them into smaller squares yields about 24 pieces which is perfect for larger crowds
• Use a sharp knife and wipe it clean between cuts for the prettiest edges
• These bars actually improve in flavor after sitting for a day as the toffee softens slightly

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There is something deeply satisfying about turning a simple box of cake mix into something that makes people close their eyes and make those happy little sounds after the first bite. These bars have become my go to for every occasion that calls for dessert but not three hours of effort.

Recipe FAQs

→ Can I use different types of cake mix?

Yes, yellow or vanilla cake mix works best, but butter pecan or spice cake mix can add interesting flavor variations. Chocolate cake mix would make these even more decadent.

→ How do I know when the bars are done baking?

The edges should be lightly golden and the chocolate topping slightly bubbly. The center will still feel soft but will set as it cools. Avoid overbaking or the base will become hard.

→ Can I make these without nuts?

Absolutely. The pecans are optional—simply omit them for a nut-free version. The toffee bits still provide plenty of crunch and texture.

→ Why do I need to let them cool completely before cutting?

Cutting while warm causes the chocolate to smear and the bars to crumble. Letting them cool allows the toffee to harden and the chocolate to set, giving you clean, neat squares.

→ Can I freeze these bars?

Yes, wrap individual bars tightly in plastic and freeze for up to 3 months. Thaw at room temperature for about an hour. The texture remains excellent after freezing.