Combine the graham cracker crumbs and unsalted butter in a blender cup and pulse or blend until the crackers are finely crushed and evenly mixed with the butter. Pour the crushed cracker mixture into a tart pan, spread it evenly, and press it down firmly by hand.

Peel the apricots and add them to a small saucepan with light brown sugar, cardamom, and lemon slices. Heat over medium heat, stirring frequently for about 15 minutes until the apricots soften and the sugar dissolves.

While the apricot mixture cools, mix cream cheese, heavy cream, and vanilla extract in a bowl with an electric mixer. Beat well until soft peaks form.

Once the apricot mixture has cooled, blend it with an electric mixer until smooth.

Pour the cream cheese mixture over the prepared crust and spread it evenly. Add the apricot mixture on top, spreading it in the center and leaving a 2-inch gap around the edges. Thinly slice 3 apricots and use them to decorate the tart.