Make the crust: Stir crushed cookies, sugar, and salt with melted butter until the mixture looks like wet sand. Press firmly into the bottom of an 8x8-inch pan or a 9-inch pie dish. Use the bottom of a measuring cup to compact it. Chill for 15–20 minutes.

Whip the cream: In a cold bowl, whip heavy cream to medium-stiff peaks. Set aside in the fridge.

Beat the base: In a separate bowl, beat cream cheese until smooth. Add powdered sugar, lemon juice, lemon zest, vanilla, and salt. Mix until creamy and lump-free.

Fold it together: Gently fold the whipped cream into the lemon-cream cheese mixture in two additions. Stop when it looks smooth and airy. Taste and add a bit more powdered sugar if you like it sweeter.

Assemble the filling: Spread the lemon filling over the chilled crust in an even layer. Smooth the top with a spatula.

Add blueberries: Scatter blueberries evenly over the filling. If using jam or lemon curd, warm slightly and drizzle over berries for a glossy finish. Sprinkle with extra zest if you love citrus.

Chill: Cover and refrigerate for at least 3 hours, or until set. Overnight is even better for clean slices.

Serve: Slice with a sharp knife. Wipe the blade between cuts for neat squares. Enjoy cold.