Design Eat Repeat

8 2022 Update: Some readers have reported their cookies being cakey. After making this recipe for years, this has also started happening to me. There's been speculation that store-bought butter has changed its formula a bit during the pandemic. Until we can properly retest this recipe, I am now recommending to melt the butter until it "pops" to make sure it's hot. This should help the cookies flatten more.
0 Preheat oven to 350℉ (you want the oven ready as soon as you're done scooping!)
1 Use a sharp knife to chop [adjustable]1/2 cup[/adjustable] of the dark chocolate chunks into small shards and slivers (Note: only chop HALF of the chunks - not the full cup we'll be adding). Set aside.
2 In a small microwave-safe bowl, add the unsalted butter ([adjustable]½ cup, i.e. 1 stick[/adjustable]) and cover with a paper towel (will help for splattering). Melt the butter for 30-45 seconds until all is melted (no chunks left). You want it hot; if you hear it "pop" then it's most likely done. *If you've made these before, see notes section for this change in 2022.
3 Pour butter into a larger bowl then add in granulated sugar ([adjustable]¼ cup) and brown sugar (½ cup) and use a spatula to stir until combined (* do not use a mixer for this recipe). Add in egg (1 large) and vanilla extract (1 ½ teaspoons), then mix. Next, add in baking soda (¼ teaspoon), baking powder (¼ teaspoon), and salt (¼ teaspoon) and mix again. Add in all-purpose flour (1 ¼ cups[/adjustable]) and mix until all the flour disappears into the dough. Note: the dough WILL be wet and sticky, this is normal.
4 Add the [adjustable]1/2 cup of chopped chocolate chunks and 1/2 cup[/adjustable] of whole chocolate chunks into the dough and mix.  Allow dough to sit for 1-2 minutes to slightly set so it's not as sticky.
5 Line a baking sheet with parchment paper. Scoop dough into 3-tablespoon sized scoops then gently roll into your hands to create a ball. Flatten the tops so that they're a thick disc vs. a round ball. See image in post for reference. Without flattening, your cookies will be thicker and more cakey.
6 Bake at 350℉ for 10-12 minutes. You want them to be slightly brown on top and look slightly underbaked (my oven was perfect at 11 minutes). 
7 Remove from oven and place entire pan on a cooling rack. Allow the cookies to cool on the hot pan for 10-15 minutes before removing them. This will allow them to finish baking on the hot pan. Once cooled, use a spatula to transfer them to a wire cooling rack.