Whisk the whole milk, vanilla pudding mix, and pure vanilla extract in a medium bowl, then fold in the finely chopped toasted pecans and 1/2 tsp. salt. Leave the pudding for about 5 minutes, until it thickens enough to mound softly on a spoon.

Beat the softened cream cheese and granulated sugar in a large bowl on medium-high speed for 2 to 3 minutes, then slowly stream in the heavy cream and keep beating. Stop when stiff peaks hold their shape and the filling looks smooth and fluffy.

Warm the caramel in a medium microwave-safe bowl for about 20 seconds total, just until pourable, then stir in the whole toasted pecans, cinnamon, and a pinch of salt. The pecans should be evenly coated, with caramel that is fluid but no longer steaming.

Spread a thin layer of the cream cheese filling across the bottom of a 13" x 9" baking dish, then arrange a layer of graham crackers over it. Add half the pudding, half the cream cheese filling, the remaining crackers, remaining pudding, and remaining cream cheese filling, then finish with the caramel pecans.

Refrigerate the assembled dessert for at least 6 hours and up to overnight, then drizzle with more caramel before serving. The crackers should feel tender when pierced, and the layers should hold together when a slice is lifted.