In the bowl of an electric mixer, beat cream cheese and ¼ cup sugar until light and fluffy, about 2 minutes.
Slowly add in heavy cream and beat until stiff peaks form.
In another medium bowl, beat milk, pudding mix, pumpkin, and pumpkin pie spice until well-mixed and thick. Start with 1 1/2 cups milk and beat until it’s the consistency of a pudding—if it’s too thick, continue to add the rest of the milk.
For Layering the lasagna
Spread a thin layer of cream cheese mixture in a baking dish.
Top with a layer of graham crackers.
Add half the pudding mixture and top with a layer of half the cream cheese mixture.
Drizzle with caramel.
Repeat.
For setting
Cover loosely with plastic wrap and refrigerate at least 4 hours and up to overnight.
For serving
Drizzle with caramel and garnish with pecans. Yum.