Brownies:

Preheat the oven to 350°F. Line a 9x9-inch baking pan with parchment paper and lightly spray with non-stick baking spray. Set aside.

In a large bowl, sift together the flour, baking powder, salt, and cocoa powder. Set aside.

In a medium saucepan, melt the butter with the oil and 1/3 cup of the sugar over medium heat, stirring frequently until the butter is fully melted. Remove from heat.

In a separate large bowl, whisk together the eggs and the remaining sugar until well combined, about 30 seconds.

Gradually add the warm butter mixture to the egg mixture, pouring in small amounts at a time while continuously whisking until fully blended.

Gently fold in the dry ingredients and chocolate chips using a rubber spatula. Be careful not to overmix—stop stirring as soon as the dry ingredients are no longer visible, as over mixing can make the brownies too cakey.

Pour the batter into the prepared pan and smooth out the top.

Bake for about 30 minutes, until the edges are set and the top is shiny with slight cracks.

Place the pan on a cooling rack and allow the brownies to cool completely before adding the ganache.

Ganache and topping:

Heat your heavy cream in the microwave for 30 seconds and in a heat safe bowl pour it over the chocolate chips. Let it sit for 1 minute and then stir until smooth.

Pour the warm ganache over the cooled brownies while it's still easy to spread. Use an offset spatula or the back of a spoon to gently smooth it into an even layer, covering the entire surface. Don't worry if it isn't perfectly smooth right away—the ganache will naturally level out as it sets. Keep the ganache within the edges of the brownies for the neatest appearance, then finish by sprinkling the candy-coated chocolate chips evenly over the top before the ganache firms up.

Transfer the brownies to the refrigerator to chill until the ganache is set and firm enough to cut, about 30 minutes. Use a hot, dry knife (I like to run my knife under hot water and then wipe it dry with a clean towel) to cut the brownies, wiping the knife clean between each cut.

If cutting into bars and adding the signature perforated line, first cut the brownies down the center to create two long halves. Lightly drag the side of an offset spatula, back of a butter knife, or skewer in a straight line down the middle length of each half to create the signature look, taking care to not drag through all the way to the brownie. Then, cut each half into 4 pieces with the indentation running crosswise to yield 8 bars total. Alternatively, you can cut the brownies into 16 squares and skip the perforated line altogether.

The brownies can be stored in a single layer in an airtight container at room temperature for up to 2 days or chilled in the refrigerator for up to 1 week.