Prepare Brownie Batter:

• Preheat oven to 350 degrees.
• Prep 9 X 13 inch baking pan with nonstick baking spray.
• Line the baking pan with parchment paper with extra on the four sides.
• To make brownies, follow the ingredients and directions listed on the back of the boxes.
• Pour the batter in the prepared baking pan.
• Set aside.

Mix Cookie Dough:

• Add the peanut butter and soft butter in a mixing bowl.
• Use the paddle attachment of the electric mixer to combine.
• Add the brown sugar, white sugar, eggs, and vanilla.
• Beat until completely mixed.
• In a second bowl add flour, baking soda and salt.
• Whisk to blend.
• Add the oats and chocolate chips.
• Beat to blend all ingredients together.

Assemble and Bake Cookie Brownies:

• Use a serving spoon to drop the oatmeal mixture over the brownie batter.
• Sprinkle the Halloween sprinkles over the top.
• Bake at 350 degrees for 25-25 minutes.
• Insert a toothpick in the center to see if it is done.
• When done, set on a counter for at least 30 minutes to cool.
• Remove from the baking pan.

Make Green Frosting:

• Using a standing mixer, beat the butter, powdered sugar, vanilla and heavy whipping cream with paddle attachment until combined, creamy and stiff.
• Beat in a few drops of neon green food coloring and mix until blended.
• Scoop the frosting into the piping bag.

Decorate Alien Cookie Brownies:

• Pipe big and small dollop on the brownies.
• Place two mini candy eyes in the frosting.
• Allow frosting to firm up before enjoying!