Line a 15X10 cookie sheet with nonstick foil, parchment paper or buttered wax paper. I like to use a jelly roll type pan so you don't have to worry about the melted butter running off the sides. Break up the graham crackers into halves or quarters sections and the line the cookie sheet with them, close together. You can break up any sections more if you need to, to fill all the gaps, they really won't show.
Place the butter and sugar in a small saucepan and melt over medium heat. Let it boil gently for 3 minutes. Remove from heat and spoon butter mixture all over the graham crackers. You can spread it around to cover evenly.
Bake at 325° for 10 minutes.
Remove from oven and cool for just a minute. Sprinkle the chocolate chips all over. Give them a couple minutes to melt and then spread chocolate evenly over graham crackers. Immediately sprinkle pecans (or other nut of your choice) over melted chocolate. Sometimes I will press down gently to make sure nuts adhere well.
Let cool until chocolate is set. Peel off backing and break up toffee into pieces. They don't have to be uniform. Enjoy.