These are really fudgey, gooey brownies. If you are a cakey brownie person (why though? Cakey brownies are obviously inferior.) these are not for you. These brownies really foxed me at first; the original recipe called for a 9" x 13" pan and I just couldn't get them to bake properly at that size. When the condensed milk was perfectly bubbly and golden brown on top, the brownies in the middle of the pan were still oozingly raw.
I solved the problem by halving the recipe and using an 8" x 8", without skimping at all on the condensed milk. This did the trick and I got soft, gooey, just-set brownies with a frankly shocking amount of swirly puddles of condensed milk through the bars and a crispy-crackly caramelized top.
They are crazy rich. I urge you to keep the flaky salt on top, even to go a little more heavy-handed with the salt than you might be thinking. The salt is going to balance the sweetness beautifully, and really make that condensed milk caramel sing. They are best served cut into tiny bite-sized pieces, and any leftovers freeze really well. If you should have any leftovers...
caramel swirl brownies:
adapted from Fine Cooking
3/4 cup butter
1/2 cup all-purpose flour
1/2 cup + 2 tbs cups cocoa powder
3 oz. semisweet chocolate, roughly chopped
1 cup + 2 tbs granulated sugar
2 tbs brown sugar
1 tsp salt
3 large eggs, cold
2 tsp vanilla extract
1/2 cup milk chocolate chips
1 tsp espresso powder (optional)
1 tin condensed milk
big pinch flaky sea salt
In a small saucepan, melt butter over medium heat. When the butter is melted, remove from heat and stir in chocolate. Let the heat from the butter melt the chocolate, stirring occasionally until fully melted and incorporated.
In the bowl of a stand mixer, whip eggs, sugars, vanilla and espresso powder on a medium-high speed. Whip until very fluffy and pale yellow, around 8 minutes. While the eggs whip, whisk together flour and coco in a medium bowl, making sure there are no clumps.
Once egg mixture is very fluffy, reduce speed to low and pour in the chocolate-butter mixture
Pour about 2/3 of the condensed milk over the top of the batter, and swirl around with a toothpick. Bake for about 10-15 minutes, until the top is starting to caramelize and bubble. Pour over the remaining milk and sprinkle with a big pinch of flaky salt. Saving some milk to add later helps make sure that you get a chewy caramelly top and it doesn't all sink into the batter.
Continue to bake for about 10-15 minutes, until all the caramel is bubbly and caramel brown.
Let cool completely and cut into small squares.