Line a sheet pan with foil and coat with cooking spray or alternatively you can use a nonstick silicon baking mat.
Preheat the oven to 400 degrees F.
Place the matzo in a single layer on the baking sheet. You may need to break it into smaller pieces to fit across the sheet pan.
Place the butter and brown sugar in a medium saucepan, bring to a boil. Boil for 3 minutes.
Pour the brown sugar mixture over the matzo and spread with a spatula to coat.
Place the sheet pan in the oven and bake for 3-5 minutes, or until bubbling.
Remove the pan from the oven and immediately scatter the chocolate chips over the top. Place the pan back in the oven for another 2-3 minutes to melt the chocolate. Spread the chocolate evenly over the top.
Place the pecans on top of the chocolate, then sprinkle the salt over the top.
If you're using white chocolate as your topping, drop it in spoonfuls on top and use a skewer to swirl it into the dark chocolate for a marbled effect.
Let the toffee sit until completely cool, either at room temperature or you can refrigerate it for 30 minutes. Cut into pieces and serve.