Preheat the oven to 350 degrees. Place the inserts into the bottom of each of the (12) cavities of a mini cheesecake pan, and spray with cooking spray. Set aside.
Place the mini oreos in the bowl of a food processor and process until coarsely ground. Place 1 cup of the ground Oreos in a small bowl, reserving the rest for garnish. Add the melted butter and pinch of salt, and stir until the cookies are completely coated with the butter.
Divide the cookie mixture equally in the prepared pan, pressing down with the back of a teaspoon to pack the crumbs in. Bake for 8-10 minutes. Cool on a wire rack.
Prepare the cheesecake filling:
Beat the cream cheese in a medium bowl until smooth, about 1 minute. Add the brown sugar, pumpkin, Greek yogurt or sour cream, egg, vanilla, and spices, and beat until smooth and well combined. Stir in the crushed Oreos,
Divide the filling evenly between the 12 cavities, leaving about 1/4" of space at the top. You will have a bit of filling leftover.
Bake on the middle rack of the oven for about 15 minutes or until set but just a bit wobbly in the center. Begin checking for doneness after 10 minutes, as oven temperatures vary considerably.
Cool 20 minutes on a wire rack, then push up through the hole in the bottom of each cheesecake and remove each one. Use a knife to loosen the sides if necessary -- I didn't have to. Remove the metal insert if they're easy to remove at this point, and cool completely in the refrigerator for a minimum of 2 hours or overnight.
Place the whipped cream n a piping bag fitted with the tip of your choice (I used 1M), and pipe over the chilled cheesecake.
Sprinkle with the remaining crushed Oreos and and garnish each with a mini Oreo cookie and enjoy!
Notes
The Oreo cookies will soften when refrigerated, so it's best to garnish the cheesecakes right before serving.