Melt butter with brown sugar over medium heat. Stir frequently until it bubbles.Pour over matzo and spread to cover. Put in the oven for a minute or two.
Sprinkle 2 cups of chocolate morsels on top and return to oven for 1 minuteto melt morsels.
Remove from oven and with a spatula spread chocolate. Sprinkle with nuts if desired.
Freeze 20 minutes until hard. Crack into pieces and store in a zipper bag in the freezer.