Place an oven rack in the center position and preheat oven to 325°F (163°C). Line a standard 12-cup muffin tin with paper or parchment liners.
Pulse about 9 full graham cracker sheets in a food processor until fine crumbs form. Measure 1 1/4 cups crumbs into a medium bowl and stir in brown sugar, cinnamon, and salt. Pour in melted butter and stir until the mixture resembles damp sand and clumps together when squeezed.
Spoon a heaping tablespoon of crumb mixture into each lined muffin cup and press down firmly using the bottom of a small flat glass or the back of a spoon. Bake for 5 minutes until toasty and set, then move tin to a wire rack to cool. Leave oven on at 325°F.
Beat softened cream cheese in a large bowl with a hand mixer on medium-low for 1 to 2 minutes until completely smooth. Add granulated sugar and flour, then beat for another minute until no grainy sugar remains. Scrape down the sides and bottom of the bowl.
Add pumpkin puree, pumpkin pie spice, remaining cinnamon, and salt. Mix on low speed until the batter is a uniform creamy orange with no white streaks. Add sour cream and vanilla extract, then mix on low until smooth. Scrape the bowl once more.
Add eggs one at a time, mixing on the lowest speed just until each egg disappears into the batter. Stop as soon as the batter looks smooth and glossy. Give the batter a few gentle folds by hand with a spatula.
Use a cookie scoop or 1/4 cup measure to divide batter evenly among the 12 cooled crusts, filling each about three-quarters full. Tap the tin on the counter a few times to release air bubbles and level the tops. Wipe away any drips on the tin.
Bake at 325°F for 22 to 27 minutes, avoiding opening the oven door during the first 15 minutes. Cheesecakes are done when edges look set and centers still jiggle slightly like gelatin, and tops look matte instead of shiny. Remove tin and set on a wire rack.
Let cheesecakes cool in the tin on the wire rack for 20 to 30 minutes until no longer hot to the touch. Loosely cover the tin with plastic wrap and refrigerate for at least 2 hours, preferably overnight.
Chill a mixing bowl and beaters in the freezer for 10 minutes. Add cold heavy whipping cream, powdered sugar, and vanilla extract to the bowl. Beat on medium-high for 2 to 3 minutes until stiff peaks form. Pipe or dollop onto each cheesecake, then drizzle with salted caramel sauce and dust with pumpkin pie spice. Serve chilled.