A grown-up evolution of a 40-year-old family peanut-butter chocolate-chip “yellow cake” bar: browned butter, 72% cacao, rum brown-sugar glaze, and fleur de sel. Identifiably the same lineage, but now it can share a plate with goat cheese ice cream and a serious wine.

Ingredients

Dry(ish)

•  1 box commercial yellow cake mix​

•  10 ounces 72% cacao chocolate chips​

•  1 cup unsweetened salted peanut butter

Wet

•  4 tablespoons (½ stick) salted butter, browned​

•  1/3 cup water​

•  2 eggs, whisked​

Glaze

•  3 tablespoons brown sugar, packed​

•  3 tablespoons salted butter​

•  3 tablespoons dark rum (for cooking) + 1 teaspoon dark rum added off-heat to refresh aromatics​

Finishing

•  Fleur de sel, for sprinkling​

Method

1. Prep and dry mix

•  Heat oven to 350 °F.

•  Butter or spray a 9×13 inch baking dish.​

•  In a large bowl, combine:

  •  Yellow cake mix

  •  72% chocolate chips

  •  Unsweetened salted peanut butter

• Mix until the chips are reasonably distributed and the peanut butter is broken up through the mix (it will not be fully smooth yet).​

2. Browned-butter custard base

•  In a small pan over medium heat, brown the ½ stick unsalted butter until the milk solids are nutty and amber; remove from heat.​

•  Stir in the 1/3 cup water to cool the butter slightly while keeping it warm and fluid.​

• In a separate bowl, whisk the eggs.

• Temper the warm butter-water mixture into the eggs slowly, whisking constantly, to form a smooth, slightly thick custard base. This should be warm but not hot enough to scramble the eggs.​

3. Form batter and bake

•  Pour the warm custard into the dry mixture. Stir until you have a thick, homogeneous batter; the residual warmth will help the peanut butter and some of the chocolate begin to integrate, giving a more uniform matrix.​

•  Scoop/spread the batter evenly into the prepared 9×13 dish.​

• Bake at 350 °F for about 30 minutes, then start checking every few minutes. 

• Visual/tactile cues for “pull time”:

  • Top is lightly cracked and matte, not glossy raw batter.

  • Edges have just pulled away from the sides of the pan.

  • Center still has a slight give when gently pressed, but no visible slosh.

  • A toothpick may sometimes come out with melted chocolate (acceptable); look for no raw batter clinging.​

  • If the center still feels too loose, you can give it a few extra minutes or pull it slightly under and rely on carryover (see below).

4. Rum brown-sugar glaze

While the bars bake, make the glaze.

•  In a small saucepan over medium–low to medium heat, melt 3 tablespoons unsalted butter.

• Add 3 tablespoons brown sugar and cook, stirring, until fully dissolved and starting to thicken into a glossy syrup.​  

• About halfway through the reduction, add 3 tablespoons dark rum. 

• Continue to simmer gently, stirring, until the glaze coats the back of a spoon and drips in a slow stream rather than watery drops.​

• Remove from heat and stir in the final 1 teaspoon dark rum to refresh the aromatics without boiling them off.​  You’re aiming for a pourable but slightly viscous glaze that will spread and lightly soak the hot surface rather than pool in corners.

5. Glaze, salt, and cooling protocol

• As soon as the cake/blondies come out of the oven and you’re satisfied with the doneness cues, drizzle the warm rum glaze evenly over the surface.​

• Immediately sprinkle a light, even “snowfall” of fleur de sel over the top so the crystals adhere to the warm glaze but do not fully dissolve. Because the peanut butter is already salted, keep this relatively restrained on the first passes.​

Carryover / coast step (recommended):

 If the center still has a bit more give than you want but the top and edges are clearly done, you can:

• Drizzle the glaze,

• Return the pan to the turned-off oven,

•  Let residual heat in the glass and crumb finish the set without further browning.​

This gives you a dense, fudgy center with an integrated rum-caramel top.

Cooling timeline (for best texture):

 Let the pan rest on a rack at room temperature for at least 30–60 minutes before attempting to cut; longer (2–3 hours) yields cleaner, less smeared cuts and a well-set center that is still pleasantly soft.​

Serving and pairing notes

• Cut into modest squares or rectangles. The crumb should be moist, fudgy, and cohesive, with visible integrated chocolate and a thin, glossy rum-caramel top layer.

• The flavor progression should read as: brown butter and peanut → dark chocolate and toffee → rum and browned sugar → sharp pops of salt from fleur de sel.​

Ideal plating (aspirational):

•  Serve slightly warm with a quenelle of goat cheese ice cream on top or along side; the tang, mild funk, and fat echo the cheese course while cutting the sweetness.​

Wine ideas:

•  A structured Corsican red (Niellucciu/Sciaccarellu blend) with bright fruit, herbal “maquis” notes, and moderate tannin; cool-cellar temperature (~55–58 °F) to keep it lifted.​

•  A semi-sweet Georgian red (e.g., Kindzmarauli) served slightly chilled (~50–55 °F)for a more dessert-wine-like pairing that still has acidity and dark-berry fruit to stand up to chocolate and rum.​