Preheat your oven to 350°F (175°C). Spread the all-purpose flour evenly on a baking sheet and bake for 5–7 minutes, stirring halfway through, until it reaches 165°F. Remove the flour from the oven and let it cool completely.

In a large mixing bowl, beat together ½ cup of softened unsalted butter, ½ cup of granulated sugar, and ½ cup of brown sugar until light and fluffy.

Add 1 teaspoon of vanilla extract and a pinch of salt, mixing well. Gradually incorporate the cooled heat-treated flour at low speed until just combined.

Pour in 1 cup of sweetened condensed milk and mix gently until fully incorporated.

Fold in 1 cup of semi-sweet chocolate chips into the cookie dough mixture until evenly dispersed.

In a microwave-safe bowl, combine ½ cup of additional chocolate chips with 1 tablespoon of vegetable oil. Microwave in 30-second intervals, stirring until melted and smooth.

Line an 8x8-inch pan with parchment paper and press the cookie dough evenly into the bottom. Pour the chocolate ganache over the cookie dough layer and smooth it out.

Chill the assembled bars in the refrigerator for at least 2 hours or overnight.

Lift the bars out of the pan using the parchment overhang and slice into squares or rectangles.