Blend the butter, sugar, egg, and cinnamon in a large bowl. Add the flour and blend until just combined.
Scoop the cookie dough into mini muffin tins OR regular sized muffin tins (both shown) that have been sprayed liberally with baking spray.
Use a pastry tamper (or fingers) to work the cookie dough into cookie cups in the tin. *Note - twisting and lifting the tamper after pressing it into the dough is the best way to release the tool from the sticky dough.
Bake the cookie cups in a preheated 350-degree oven for 18-20 minutes.
Remove the cookie cups from the oven and press again with the tamper (if needed) to redefine the cups.
Cool the cookie cups completely on a baking rack.
To make the pumpkin cheesecake filling;
In a large bowl, blend together the softened cream cheese, vanilla, cinnamon, and nutmeg until creamy.
Blend in the pumpkin purée and Greek yogurt until completely incorporated.
Spoon the pumpkin cheesecake filling into a large zip-top bag and work the filling into one of the bottom corners.
Snip a small corner off of the bottom of the bag and carefully squeeze the pumpkin cheesecake filling into the baked and cooled cookie cups.
Dust the tops of the Pumpkin Cheesecake Tartlets with ground cinnamon or freshly grated nutmeg before serving.
Notes
This recipe makes 12 regular size muffin tartlets OR 24 mini size muffin tartlets. The calories and nutrition label for this recipe is for regular size tartlets.