Preheat oven to 350 degrees and line a muffin pan with 8 cupcake liners. In a large bowl, whisk together eggs, oil and room temperature brewed coffee. Add dry organic brownie mix and use a spatula to mix until smooth.
Fill each cupcake liner 2/3 full with batter. Bake 13-15 minutes until a toothpick inserted in the center comes out clean. Remove from oven and cool completely on a wire cooling rack.
To make the frosting, in a large bowl, use an electric mixer to blend together the butter and yogurt until combined. Add the peppermint extract and dry organic frosting mix, then blend until smooth and creamy, about a minute.
Place frosting into a piping bag or plastic storage bag fitted with a star piping tip. Snip off the end of the plastic bag, then pipe frosting onto each brownie cupcake. Garnish with a sprinkle of crushed peppermint.