Slice the apple about 1/3-inch thick. Lay flat on a cutting board. Use a small star cookie cutter to slice the apple into the shape of a star. Set aside.
Start assembling your Christmas tree from the trunk up. Use crackers to create the trunk.
Lay two sprigs of rosemary horizontally to create the base of the tree.
Then add cubes of cheddar cheese in a straight line from edge to edge of the platter.
Continue with the salami, red grapes, provolone, prosciutto, green olives, and pretzels, making each row narrower than the row before until you finish with the dried cranberries at the top. Place more sprigs of rosemary in between any sections that have round ingredients, like grapes or olives, to keep them from rolling onto other sections.
Once you've finished the tree, top with with the apple star that you made earlier.
Serve with additional crackers and pretzels.