Place all the fruit in a bowl, cover it with water, and add vinegar. Let the fruit sit for about three minutes, then strain it using a colander. Rinse the fruit lightly under running water, then set it aside.

Purchase the pandoro at the Italian market. Inside the package, you'll find the tall, octagonal bread and the confectioners' sugar in a large plastic bag.

Open the bag and pour in all the confectioners' sugar. Then, fill the bag with air, twist the top to seal it, and shake to coat the bread evenly.

Transfer the sugar-coated pandoro to a cake stand. Using a bread knife, slice it from the top down, spacing the slices about 1.5 inches apart. Slice slowly to make the slices as even in thickness as possible.

Starting from the top slice of bread, work your way down to the bottom slice, twisting each piece slightly so that the star's corners do not overlap. This will give the pandoro its Christmas tree shape.

Attach the whisk attachment to your stand or hand mixer. Then, add the heavy cream, condensed milk, citrus juice, zest, and salt in a bowl. Whip the mixture until stiff peaks form. Fill the pastry bag with cream.

Set aside the bread slices except for the bottom layer. The center of the bottom layer, pipe the cream in a circular motion. Sprinkle berries sparingly in the center, then place a piece of sliced bread on top. Arrange the star corners so that they overlap and form a tree shape. Repeat this process up to the top layer. Decorate the top layer with cream and fruit as shown in the photo. Pipe a little cream into the space at the very tip of the star and place a piece of fruit on top.

Finish by sprinkling powdered sugar over the entire surface.

Cut the cake into four pieces using the inner points of the star as your guide. The cake will be cut into pointed heart shapes. Serve with the remaining cream and fruit.