In a large bowl, combine the graham cracker crumbs, brown sugar, cinnamon, and salt. Pour in the melted butter, and mix until it creates a wet, sandy texture.

Transfer the mixture to a 9-inch springform pan, and press into an even layer across the bottom and up the edges a half inch.

Bake for 8-10 minutes or until lightly browned. Remove from the oven, and allow to cool completely before adding the filling.

Place the softened cream cheese and granulated sugar in the bowl of a stand mixer. Use a paddle attachment to beat until creamy and free of lumps.

With the mixer running on low, add the eggs. Then slowly stream in the heavy cream.

Sift in the cornstarch a little at a time. Once all of the cornstarch has been mixed in, stop the mixer.

Place 1 cup of M&Ms into a food processor. Pulse a couple of times to crush the candies. Use a spatula to fold the chopped M&Ms.

Pour the cheesecake filling into the cooled crust, and smooth the top flat.

Find an oven safe dish that is larger than your springform pan. This dish will be used for your water bath. Place the springform pan into the larger dish. Very carefully fill the larger baking dish with very hot water only to about 1 inch deep. Be careful to not go over the top of the aluminum foil or splash water onto the cheesecake.

Carefully transfer the pan to the oven, and bake for 80 to 90 minutes. The sides of the cheesecake should be set, and the center should jiggle slightly. The internal temperature of the should be 145°F-150°F on an instant read thermometer.

Turn the oven off but leave the cheesecake inside while keeping the door ajar for 60 minutes. This allows the cheesecake to cool down slowly and helps prevent cracking.

After an hour, remove the cheesecake from the oven and from the water bath. Allow the cheesecake to cool completely at room temperature, then cover with a layer of plastic wrap and chill in the refrigerator for at least 6-8 hours.

When ready to serve, remove the cheesecake from the refrigerator. Run a knife or thin spatula around the edge of the cheesecake to loosen it from the pan. Remove the outer ring of the pan gently.

Using a heart shaped cookie cutter, gently imprint the shape of a heart on the top center of the cheesecake. (Or you can use a toothpick to draw a heart in the center of your cheesecake.) With the cookie cutter still in place, dust the top of the cheesecake with powdered sugar.

Remove the cookie cutter and place M&M's around the heart shape. Continue to fill the heart in with M&M's. Place the cheesecake on a serving platter, then pipe whipped cream peaks all around the top edge of the cheesecake.

Serve chilled. See post for storage options.