In bowl, combine cream cheese, 1 cup powdered sugar, mint extract, and green gel coloring. Beat until smooth.
Gradually add remaining powdered sugar and mix until firm, scraping sides.
Scoop teaspoon‑sized rounds, roll into balls, then use a spoon or end of measuring spoon to press a shallow indentation in center of each.
Chill the shells to firm up (≈30 minutes).
Meanwhile, in a heatproof bowl, pour the heavy cream over chocolate chips. Let sit 2 minutes then stir until smooth ganache. Chill or thicken slightly.
Fill each shell indentation with ganache.
Chill for another ~30 minutes to set ganache. Serve cold.