Use a sharp knife to trim off the crusts of the sandwiches, creating clean edges.
In a mixing bowl, whip the heavy cream using an electric mixer on medium speed until it thickens. Add the sugar and vanilla extract, then continue whipping until stiff peaks form. Set aside.
Lay out 8 slices of bread on a clean work surface and spread a thin layer of heavy cream on them.
Arrange a layer of fruits on top, covering them evenly. You can mix and match different fruits according to your preference.
Take the whipped cream mixture and spoon it over the fruit layer, spreading it evenly to cover the entire surface.
Place the remaining four slices of bread on top of the cream layer, pressing down gently.
Wrap firmly with plastic wrap and put the fruit sandwiches on a plate or sheet pan.
Make sure to mark the direction of the diagonal fruit line, as this will guide you when cutting the sandwich later.
Place another plate or sheet pan on top of the sandwiches, and place something heavy and firm on top to press them evenly. Allow the sandwiches to rest in the refrigerator for at least an hour.
Cut the sandwiches into desired shapes, such as triangles or rectangles. You can also leave them as whole sandwiches if you prefer.
Serve the Fruit Sando immediately, or refrigerate for a few hours to allow the flavors to meld together.