Preheat an oven to 350ºF.
In a small bowl, combine graham cracker crumbs, sugar and butter. Stir in chopped M&M’S® Pastel Chocolate Candies.
Lightly coat mini-cheesecake pans with nonstick baking spray. Add approximately 1 tablespoon of the graham crumb mixture to each cheesecake vessel and press to form a crust on the bottom.
Bake crusts about 6 minutes or until they just begin to turn light brown. Remove from oven and set aside.
In a stand mixer using a paddle attachment, beat cream cheese until smooth. Slowly add sweetened condensed milk until fully combined. Slowly add in key lime juice until mixture starts to thicken.
Pour approximately 1½ tablespoons of filling onto each crust.
Refrigerate for at least 6 hours, or overnight.
Remove from cheesecake pan and top with lime zest. Serve immediately.