This recipe is adapted from Lisa Falasca, who used to make these and send them into work with her son Danny. I had the good fortune of sitting right near him. I spent a year experimenting with her recipe—think: swapping in brown butter, cutting back on flour, adding alt sugars—only to land very close to her original ingredient list. Try these out, and you'll see why.
"I give a lot of recipes a try," says Lisa. "Some are 'one and done' and others are 'keepers.' Everyone decided this was a keeper." (Lisa's recipe is itself an adaptation from the one on Life, Love & Sugar—she tweaked it to make the base more like her go-to chocolate chip cookie dough.) —Ella Quittner
In a bowl, combine the flour, cornstarch, salt, and baking soda. Mix with a fork to distribute everything.
Cream butter and sugar together in the bowl of a stand mixer or in a large bowl with a hand mixer for several minutes, until very light and fluffy. Add the egg, vanilla, and banana. Mix to combine, then scrape down sides and bottom of bowl.
Add the dry ingredients and chocolate chunks. Mix just to fully combine, but then stop to avoid over-mixing. Refrigerate 1 hour, loosely covered with saran wrap.
Meanwhile, heat oven to 350°F. Line two baking sheets with parchment paper.
Use a 1.5-ounce scoop to make mounds of dough on cookie sheets spaced about 3 inches apart. Sprinkle each with a big pinch of flaky salt (don’t skimp—it really balances these out). Bake 14 to 16 minutes, until cookies are puffed up, starting to turn golden around the edges, and the middles look set. Let cool on trays a few minutes, then transfer to cooling racks. Repeat with remaining batter.
Ella Quittner is a contributing writer and the Absolute Best Tests columnist at Food52. She covers food, travel, wellness, lifestyle, home, novelty snacks, and internet-famous sandwiches. You can follow her on Instagram @equittner, or Twitter at @ellaquittner. She also develops recipes for Food52, and has a soft spot for all pasta, anything spicy, and salty chocolate things.