Preheat oven to 350°F. Line a large baking sheet with parchment paper.

In a large microwave-safe bowl, microwave the chocolate and oil in 20-second intervals, stirring in between until melted and smooth. Let cool 5 minutes.

Whisk in the eggs and vanilla extract. Whisk briskly for 90 seconds. This helps achieve the pretty crackles on top of the cookies!

Add the brownie mix and use a spatula to fold it in until dough is thick and smooth.

Use a 1/3 cup measuring cup or scoop to scoop eight dough balls. Shape each scoop with your hands into a large thick disk (about 1” high). Allow 3” between each scoop to prevent the cookies from fusing during baking. I was able to fit six cookies on one baking sheet.

Check notes for information on how and why to bake a test cookie!

Bake one sheet at a time for 15-17 minutes until the cookies are puffed and crackled on the edges. Note: the cookies will appear to be quite gooey, but they harden up as they cool. If you keep baking, they will be too hard once cool.

An instant-read thermometer can be helpful. So long as the cookies measure at least 165°F, you can pull them from the oven and let them cool. Allow cookies to cool completely before topping.

Whisk together the heavy cream, pudding mix, sugar, and vanilla extract gently for 1-2 minutes until the pudding mix is dissolved. Then use a hand mixer on low speed with the whisk attachment to whip the mixture until it is thickened to soft or medium peaks. Don’t over-whip! Store in fridge until cookies are cool enough to frost.

Scoop 3 tablespoons (I use a cookie scoop for this) of vanilla mousse per cookie and place in the center of the cooled cookies. Drizzle with hot fudge sauce (slightly warmed so that you can drizzle it!) using a spoon or piping bag. Top with plenty of sprinkles and a cherry on top!