For the caramel sauce: Combine the cream, apple juice, cloves, cinnamon, star anise, ginger and nutmeg in a medium saucepan, and bring to a simmer. Remove from the heat and let steep for at least 20 minutes. Set aside and keep warm while you make the caramel.
Combine the sugar, 1/2 cup water, and the cider vinegar in a medium saucepan over high heat, and cook without stirring until it reaches a deep amber color, about 8 minutes. Slowly strain in the warm cream, whisking constantly; continue whisking until smooth. (Be careful! The caramel will bubble up as you add the cream.) Whisk in the apple schnapps and cook for 30 seconds longer. Transfer to a bowl and keep warm. (The sauce can be made 2 days in advance and refrigerated. Reheat over low heat before serving.)
For the pancakes: Preheat the oven to 250 degrees F. Place a baking sheet with a rack in the oven to heat.
Whisk together the flour, brown sugar, granulated sugar, baking powder, baking soda, cinnamon, nutmeg, cloves and ginger in a large bowl.
In a medium bowl, whisk together the eggs, buttermilk, ricotta, pumpkin and 2 tablespoons melted butter. Add the wet ingredients to the dry ingredients, and whisk until just combined; do not overmix. Let the batter sit at room temperature for at least 15 minutes and up to 1 hour.
Heat a large nonstick pan or griddle over medium-low heat. Brush with melted butter or spray with nonstick spray. Drop a scant 1/4 cup of the batter onto the pan; cook until small bubbles form on the surface and at the edges and the bottom is lightly golden brown, about 3 minutes. (Adjust the heat if the bottom browns too quickly.) Flip, and continue cooking until golden brown on the reverse side, another 2 or 3 minutes. Remove to the rack in oven to keep warm. Repeat with remaining batter.
Serve the pancakes with a drizzle of caramel sauce and a dollop of creme fraiche.