1. Preheat the oven to 300 degrees F. Line 18 muffin cups with paper liners. Place 1 whole cookie in the bottom of each lined cup.

2. In a large bowl, beat the cream cheese, granulated sugar, brown sugar, and 1/4 teaspoon fine salt on medium-high speed until smooth and creamy, 2 to 3 minutes. Scrape down the sides, reduce speed to low and beat in the eggs, 1 at a time, until combined. Beat in 1/3 cup sour cream and heavy cream. Stir in the pumpkin puree and pumpkin pie spice until smooth. Divide evenly among cookie-lined paper cups, filling almost all the way to the top.

3. Bake until the filling is just set, 40 to 45 minutes. A sharp knife inserted into the center will come out moist, but clean. Top each cheesecake with some of the remaining 1 1/4 cup sour cream, about 1 heaping tablespoon, using a spoon to gently spread. Cool completely in tins on a wire rack. Refrigerate until cold, 4 hours, or overnight. Top with a dusting of pumpkin pie spice.