No-bake cheesecake flag cake

Mix graham cracker crumbs, butter, sugar and a couple of spoons of cocoa; press firmly and evenly into a rectangular casserole dish; refrigerate about half an hour.

Mix room-temperature cream cheese and mascarpone with lemon zest, a little lemon juice and a big splash of real vanilla.

Whisk white sugar and very cold heavy cream just to peaks without overmixing; whisk into the cheese mixture until smooth.

Spread over the crust, smooth, tap to settle, wrap and refrigerate at least three or four hours until completely firm.

Lay halved strawberry stripes, bottom row first then the top row two thirds across, then fill between; fill the top left with blueberries, dimple up.

Cut chilled with a square spatula.