In a bowl, mix graham cracker crumbs, brown sugar, salt, and melted butter until it resembles wet sand.

In a separate chilled bowl, whip 1 cup of heavy cream until stiff peaks form. Set aside.

In a large bowl, beat softened cream cheese until smooth. Add sweetened condensed milk and beat until combined.

Mix in the key lime juice, vanilla extract, and lime zest. The mixture will thicken slightly.

Gently fold the whipped cream into the key lime mixture until fully incorporated and light.

Press 2-3 tablespoons of the graham cracker crumble into the bottom of each mason jar.

Pipe a thick layer of the key lime filling over the crumb base. Add another layer of crumbs and a drizzle of caramel if desired, then another layer of filling.

Refrigerate the jars for at least 2 hours to set.

Before serving, top generously with whipped cream, a caramel drizzle, extra graham crumbs, and a fresh lime wedge.