Step 1: Make whipped cream by combining heavy cream, powdered sugar, vanilla, and cinnamon. Beat until soft peaks form.
Step 2: Make ganache by placing chocolate chips in a bowl and pouring hot cream over them. Let sit, then whisk until smooth.
Step 3: To assemble the cake, place a matzo cracker on a cooling rack inside a sheet pan. Spread ganache and whipped cream on top. Repeat the process with additional crackers.
Step 4: Pour extra ganache over the icebox cake, covering all sides. Top with chocolate shavings. Refrigerate until the cracker layers soften to become cake-like, about 4 hours. Enjoy the delightful matzoh creation!