Prepare the brownie mix according to the package's instructions.
Either grease or line your mini muffin tin with 24 muffin paper liners.
Spoon the brownie mix into the muffin tin.
Bake at 350F for 18-20 minutes.
Immediately, gently press the Reese’s peanut butter cups into the brownie bites. Wait a few minutes while the chocolate peanut butter cups begin to melt from the heat of the brownie bites.
In the meantime, slice the pretzels in half to create antlers. Set aside.
Place a red M&M on the melted chocolate of the peanut butter cup for the nose.
Then, take two of the cut pretzels and place them above the M&M on the melted chocolate.
Place two candy eyes over the bottom of the antlers.
Let cool for a few hours at room temperature until the chocolate has hardened. Alternatively, you can place the cookies in the refrigerator to harden quicker.