Ingredients
Equipment
Method
- Preheat oven to 350°F. Line a 9 inch square baking pan with parchment paper, leaving some overhang on two sides so you can lift the bars out later for easier slicing.
- In a medium bowl, whisk together the flour, malted milk powder, baking powder, and kosher salt.
- In the bowl of a stand mixer fitted with the paddle attachment, cream the butter and both sugars on medium speed for about 10 minutes, until very pale, fluffy, and doubled in volume, scraping down the sides as needed.
- With the mixer on low, add the eggs one at a time, mixing until incorporated, then add the vanilla. Scrape down the sides. Add the dry ingredients in two additions, adding most of the chopped chocolate with the second addition. Reserve about 1 to 2 tablespoons of chopped chocolate for the top. Mix on low until just combined.
- Using an offset spatula, transfer the batter to the prepared pan and roughly smooth the top. Scatter the reserved chocolate over the top and sprinkle lightly with flaky salt.
- Bake until the edges are maple colored and the center is golden, with a soft, quaking core that still leaves wet residue when a toothpick is inserted into the center, 26 to 28 minutes.
- If you want to serve these right away, spoon them warm from the pan like a sticky, gooey pudding into a sundae glass or small bowl. For clean bars, let cool in the refrigerator or freezer until cold to the touch. Use the parchment overhang to lift the bars out of the pan, then slice into squares. I like a mix of small and larger bars because these are rich. Serve at room temperature for a super soft, doughy texture, or cold for a firmer chewy bar.
Notes
Malted milk powder note: I used King Arthur malted milk powder, but Carnation is often easier to find in grocery stores. Look near the baking aisle, cocoa, chocolate syrup, or drink mixes.
Chocolate note: I used a mix of milk chocolate bar and dark chocolate bar. Chopped chocolate bars are best here because they melt into soft pockets and little puddles. Chocolate chips can work in a pinch, but they are made to hold their shape, so they will not melt the same way. Since gooey is the whole point, chocolate bars are worth buying.
Pan note: A 9-inch square pan is best if you want clean bars. In a pinch, a 9-inch pie pan will work too, especially if you plan to serve the bars warm with a spoon. Once chilled, you can still cut them, but expect squares from the center and a few uneven edge pieces.
Salt note: Go light with the flaky salt garnish. A little makes the chocolate taste better, but too much can take over fast. If you are serving people who do not love salt on dessert, use just a tiny pinch or leave it off a few pieces.
Chocolate topping note: Save 1 to 2 tablespoons of chopped chocolate before mixing the rest into the dough. Scatter those pieces on top before baking so the bars look prettier and have a few visible melty chocolate spots.