• Preheat the oven to 400 degrees Fahrenheit. Line a baking sheet with parchment paper and set aside.
• Measure out 1 ½ cups milk. Add in 1 ½ tablespoons white vinegar. Mix with a spoon and let sit for 5-10 min. Stir again.

  The milk should appear chunky and that’s normal. This is our homemade buttermilk. Set aside.
• In a large bowl, whisk together the 2 cups multipurpose gluten free flour, 1 cup cocoa powder, ¾ teaspoon baking powder, 1 teaspoon baking soda and ½ teaspoon kosher salt until combined.
• In a small bowl, using a spoon, mix together the 2 rounded tablespoons cornstarch (26 grams) and 3 tablespoons water until thin and watery. It will be thick and tacky at first.
• In a large bowl of an electric mixer fitted with the paddle attachment, beat the ½ cup unsalted butter or vegan baking stick and the 1 ¼ cups light brown sugar until soft and creamy. About 1-2 minutes.
• Slowly beat the cornstarch water mixture, the homemade buttermilk and the 1 teaspoon pure vanilla extract into the creamed butter and sugar. Beat until combined.
• Slowly add in the gluten free flour mixture to the wet ingredients, a little at a time, and beat until just combined. 
• Using an ice cream scoop or a large 2 ounce cookie scoop, scoop the batter onto prepared baking sheets making sure to leave 2 inches in between each scoop.
• Get your fingers wet and gently using your fingers, press down the batter to make a dome instead of a ball.

  Gluten free batter has a way of staying exactly as it is placed down, so if you leave it in a ball shape or misshapen, that’s how it will end up when baked. 
• Bake for 12-13 min until risen and springy when carefully poked.
• If they come out of the oven not perfectly round, carefully use a round cookie cutter to trim off any misshapen parts.
• Let them cool on the baking sheet and after a few minutes transfer to a cooling rack.

Make the Strawberry Frosting

• Make the frosting while the whoopie pies are baking.

  In a small saucepan set over medium heat, combine the 1 ¾ cups quartered strawberries and ¾ cup granulated sugar. Stir constantly for about 5-8 minutes until the strawberries have liquified a bit and the sugar has dissolved. Use the back of your spoon to mash the strawberries apart.
• Set a strainer or a mesh colander over a bowl and strain the strawberry liquid. You don’t want any of the seeds, you just want the liquid. You should have about 4 tablespoons of liquid.
• With the paddle attachment of an electric mixer, or using a large bowl and a hand mixer, beat the ½ cup room temperature unsalted butter until creamy. About 2-3 minutes.
• Slowly beat in the 4 cups confectioners’ sugar, strained strawberry liquid (4 tablespoons), 1 pinch kosher salt and 1 teaspoon pure vanilla extract. Beat until smooth and combined.

  Slowly add in the 3 tablespoons water a little at a time until you get the desired consistency. You may not need to use all the water.

  If the strawberry liquid solidified a bit prior to using, that’s ok. Just use a spatula to scrape it into your mixing bowl.
• Using a butter knife or a small spatula, frost the flat side of half the little cakes. Place the other flat side of the unfrosted cakes on top. Enjoy!