Preheat the oven to 350 °F (175 °C). Line a baking sheet with a piece of parchment paper.
In a large mixing bowl with a stand mixer or electric hand mixer, beat together the fat, brown sugar, and granulated sugar until light and fluffy. Beat in the eggs or applesauce and vanilla until well combined.
1 cup (225 grams) unsalted butter, 1 cup (200 grams) brown sugar, 1/2 cup (100 grams) granulated sugar, 2 large eggs, 1 tablespoon vanilla extract
Sprinkle the baking soda and salt on top, beat until combined, and then add in the oat flour on low speed.
1 teaspoon baking soda, 3 3/4 cups + 2 tablespoons (350 grams) store-bought gluten-free oat flour, 1 teaspoon salt
Stir in 1 3/4 cups (300 grams) of chocolate chips until combined (ignore the quantity listed below - it's a technical error I can't change).
2 1/4 cups (383 grams) semi-sweet chocolate chips
Form 1/4 cup (75-gram) balls and press the remaining chocolate chips on top (ignore the quantity listed below - it's a technical error I can't change).
2 1/4 cups (383 grams) semi-sweet chocolate chips
Place 4" apart on the prepared baking sheet.
Bake for 12-16 minutes or until lightly browned around the edge.
Let cool completely on the baking sheet. Store cooled cookies in an airtight container for up to 5 days.