Gradually add heavy cream 1 tablespoon at a time and beat after each addition.
3 tablespoons heavy cream
Add peppermint and vanilla extracts and mix everything together.
1 teaspoon peppermint extract, ½ teaspoon vanilla extract
Gradually add more powdered sugar until mixture is stiff and holds its shape.
Place the peppermint mixture on a piece of parchment paper. Roll into a log about 2 inches around. Put the log in the freezer to chill for 20-30 minutes, or in refrigerator overnight.
Once the dough is chilled get the log out and unwrap it. Use a sharp knife to cut it into pieces about ½ inch thick. Roll each piece into a ball. Use powdered sugar on your work surface if dough is sticky.
Flatten each peppermint round into a circle using a drinking glass to squish the peppermint. Put the round peppermint centers on parchment paper or a silicone line baking sheet. Put the tray in the refrigerator while you melt the chocolate.
Put the chocolate chips and coconut oil in a microwave safe bowl and heat for 30 seconds. Then stir to melt the chips. Continue to heat and stir the chocolate for 20-30 seconds at a time until it is almost completely melted. This should take 1 1/2 - 2 minutes.
1 12oz bag of dark chocolate chips, 1 tablespoon shortening
Once the chocolate is almost melted stir until it completely melts and is smooth. Now it is ready for coating.
Prepare another cookie sheet with parchment paper or a baking mat.
Take the patties a few at a time from the refrigerator and dip into the chocolate. Shake the patties gently and let any excess chocolate drip back into the bowl.
Put the dipped patties on the cookie sheet and let them sit until fully hardened.
Notes
Store the peppermint patties in airtight container for up to 2 weeks. They don't have to be refrigerated, although they can be.