Prepare the Crust:
In a medium bowl, mix the graham cracker crumbs, brown sugar, and melted butter until the texture is like wet sand. Pour into a 9-inch or 10-inch springform pan. Press down tightly using the bottom of a measuring cup to form a firm crust that goes slightly up the sides. Freeze for 10–20 minutes.

Whip the Cream:
In a chilled bowl, use a hand or stand mixer to whip the cold heavy cream until stiff peaks form (about 4–5 minutes). Set aside.

Make the Filling:
In another large bowl, beat the softened cream cheese and granulated sugar on medium speed until completely smooth (2–3 minutes). Scrape down the sides. Add the confectioners’ sugar, sour cream, lemon juice, and vanilla. Beat again until fully combined and creamy.

Fold in Whipped Cream:
Using a spatula, gently fold the whipped cream into the cream cheese mixture. Be careful not to deflate the whipped cream.

Assemble and Chill:
Remove the crust from the freezer. Pour the filling over the crust and smooth the top with an offset spatula. Cover tightly with plastic wrap or foil and refrigerate for at least 6–8 hours (overnight for best results).

Serve:
Remove from springform pan. Slice with a clean sharp knife (wipe between each cut for cleaner slices). Top with fruit, sauce, or whipped cream as desired.