In a medium bowl, combine graham cracker crumbs with melted unsalted butter. Mix until evenly moistened. Press firmly into the bottom of a 9-inch springform pan. Chill for at least 30 minutes.

In a large bowl, beat softened cream cheese until smooth and creamy, about 2-3 minutes. Gradually mix in granulated sugar until combined. Add heavy cream, fresh lemon juice, and lemon zest, folding gently until well incorporated.

Pour the creamy filling over the chilled crust. Use a spatula to smooth the top and ensure it sits evenly.

Cover with plastic wrap and refrigerate for at least 6 hours, preferably overnight, allowing the cheesecake to firm up.

Run a paring knife around the edges to loosen. Carefully release the sides of the pan. Garnish with whipped cream and lemon zest or slices before serving.