Preheat oven to 375 degrees Fahrenheit. Line a large cookie sheet with foil, either two layers or one layer foil and a second layer of parchment – makes for an easy cleanup. 

Line bottom of pan evenly with matzo boards, cutting extra pieces of matzo, as required, to fit any spaces on the cookie sheet as evenly as possible. 

Combine margarine or butter and brown sugar, even parts, in a medium to large heavy-bottomed saucepan; the mixture will become very hot – be careful to avoid spatters. Cook over medium heat, stirring constantly, until mixture comes to a boil and turns into caramel. Continue cooking three more minutes, stirring constantly. Remove from heat and pour over matzo. 

Place in hot oven and immediately reduce heat to 350 degrees Fahrenheit. Bake 15 minutes, checking every few minutes to make sure mixture is not burning (if it seems to be browning too quickly, remove from oven, lower heat to 325 degrees Fahrenheit, and return to oven). 

Remove from oven and sprinkle matzo boards immediately with chopped chocolate or chips. Let stand five minutes, then spread melted chocolate over matzo using a spatula or large spoon. 

While still warm, cut into squares or odd shapes. Chill in refrigerator until set. (Optional: sprinkle top with chopped white chocolate or sprinkle toasted chopped almonds over warm chocolate as it sets.)