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Milk Bar Pie Bars

Excerpted from ‘All About Cookies: A Milk Bar Baking Book’

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Henry Hargreaves

Makes 9 squares

Ask anyone on my team my top two questions when we’re tasting a potential new creation for the bakery, and they will tell you they are:

1. Think it could be a little sweeter?

2. Can you give it more goo?

It’s no surprise that this dense, sweet, gooey monster is a deep part of Milk Bar’s flavor and textural heritage and is also the one that best represents what excites me about this world. I love that its look is unassuming and its composition impossible to wrap your head around — two of my favorite qualities in an excellent human and a baked good. This bar is my go-to recipe when I don’t feel like going to pie town. It turns the classic Milk Bar Pie ratio upside down: This is about 2 parts toasted oat cookie crust to 1 part gooey, buttery filling. And no one’s mad at it.

Tip: If you don’t have freeze-dried corn (and therefore can’t make corn powder), substitute with corn flour, all-purpose flour, or anything flavorful you can grind down (pretzel powder is usually my stand-in). It’s not exactly the same, but likely only you will know the difference.

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Toasted Oat Crust:

  • 4 tablespoons unsalted butter, softened
  • 3 tablespoons light brown sugar
  • 1½ tablespoons sugar
  • 1 large egg
  • ¾ cup rolled oats
  • ¼ cup flour
  • ½ tsp kosher salt
  • Pinch of baking powder 

Gooey Butter Filling:

  • 1 cup sugar
  •  ½ cup light brown sugar (packed)
  • 2 tablespoons milk powder
  • 1 teaspoon corn powder
  • ½ teaspoon kosher salt
  • 1½ sticks (12 tablespoons) unsalted butter, melted
  • 1 teaspoon vanilla extract
  • 6 large egg yolks
  • Confectioners’ sugar, to finish


Heat the oven to 350°F. Pan-spray an 8×8-inch square baking dish.

Toasted Oat Crust: 

In a large bowl, mix together the butter, brown sugar, and sugar with a spatula until well combined. Mix in the egg and stir until well combined, scraping down the sides of the bowl as you go. Add the oats, flour, salt, and baking powder, and mix just until combined. Pour this mixture into the greased baking dish and use a spatula to evenly spread the mixture, fully covering the dish’s bottom.

Bake at 350°F until the edges of the crust are golden brown, about 20 minutes. Cool at room temperature for 10 minutes. Leave the oven on.

Gooey Butter Filling: 

In a large bowl, whisk together the sugar, brown sugar, milk powder, corn powder, and salt. Whisk in the melted butter, vanilla, and egg yolks and stir until smooth. Try not to aerate the batter; mix slowly and gently. Pour this mixture on top of the oat crust, spreading evenly to all sides of the baking dish, covering the bottom layer entirely.

Bake at 350°F until the top and edges are golden brown and the bull’s-eye center is still a bit jiggly, about 20 minutes. While baking, make room in your freezer for this baking dish.

Remove from the oven and ideally transfer the pan to an empty freezer to cool completely. This not only cools down the greatest bite you might ever bake, but also ensures that all the steam pockets subside. The result is a dense and gooey bar cookie, which is also much easier to portion when frozen.

Cut into 9 squares. Dust with confectioners’ sugar before serving, if desired. Store in an airtight container or plastic wrapped on the counter for up to five days or in the fridge for up to two weeks. Feel free to hide these in the freezer, no one will go looking for them there (wink).

Adapted from All About Cookies. Copyright © 2022 by MomoMilk, LLC. Photographs copyright © 2022 by Henry Hargreaves. Published by Clarkson Potter, an imprint of Random House.


Bake With Christina

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Random House

Two more recipes from All About Cookies for AARP members to try:

Crunchy Confetti Cookie

The sprinkles are the star of the show in these confetti cookies gone crispy.

Chocolate Peppermint Pretzel Snaps

Snaps are a Milk Bar invention — cookie on the bottom with a spreadable layer on top, paired with something salty or crunchy then dunked in something to merge the flavors. And these are the very first snap in Milk Bar history.

Read about Christina Tosi's latest cookbook, All About Cookies.


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