Preheat the oven to 375℉. Line two baking sheets with Silpat liners or parchment paper.
In the bowl of a stand mixer, combine brown and white sugar, butter, shortening, salt, vanilla extract, vinegar, and baking soda. Beat until smooth and creamy and ingredients are incorporated.
⅔ cup light brown sugar, ⅔ cup granulated sugar, 8 tablespoons unsalted butter, ½ cup vegetable shortening, ¾ teaspoon salt, 2 teaspoons pure vanilla extract, 1 teaspoon white vinegar, 1 teaspoon baking soda
Beat in the egg until thoroughly mixed in, scraping the side and bottom of the bowl.
1 large egg
Mix in the flour and then the chocolate chips.
2 cups flour, 1 bag 11.5 ounces semisweet chocolate chips
Cut croissants in half and place on prepared baking sheet. Using a cookie scoop, scoop the dough and place it on the bottom of the croissant. Using a rubber spatula, spread the cookie dough on the bottom croissant. Put the top on the cookie dough. Scoop two dollops of cookie dough and place on top of the croissant. Spread across the top, leaving a bit of the croissant exposed.
4 large store-bought croissants
Bake cookie croissants 12 - 14 minutes.
Remove from oven and move to a cooling rack. Serve warm or at room temperature.
If there is leftover cookie dough, make cookies!