In a medium saucepan over low heat, whisk together lemon juice, sugar, and eggs until smooth. Stir continuously for 10 minutes until thickened. Remove from heat, stir in butter, then strain through a sieve. Refrigerate until chilled.

Preheat oven to 350°F (optional). Pulse graham crackers into fine crumbs. Combine with melted butter, then press firmly into bottoms of 20 mini cups. Reserve some crumbs for garnish.

In a bowl, beat cream cheese with sugar until creamy, then fold in cooled lemon curd. Whip heavy cream to soft peaks and fold into lemon mixture until combined.

Layer cheesecake mousse into cups, add a layer of lemon curd, then top with more mousse, creating layers.

Sprinkle reserved crumbs on top, cover, and refrigerate for at least an hour before serving.