Line cookie sheet with tin foil and lay saltines touching in a single layer. (If there is excess room on the cookie sheet, fold up the foil so the crackers stay close together and the butter doesn't seep away from the crackers.)
Combine sugar and melted butter (the sugar will not dissolve). Evenly distribute mixture, being sure to cover all the crackers with some butter and sugar.
Bake for 10-15 minutes at 350 degrees. While baking, the butter will start to look frothy and bubbly. Be sure to remove from oven as soon as butter turns a light golden brown.
Once removed from the oven, push crackers together as they may of moved or overlapped while baking. Immediately sprinkle with peanut butter and chocolate morsels. Let sit a few minutes to melt then use a spatula to spread it over all the crackers.
Top with pecans (pressing them with your hands into the chocolate will help them stick a little better) then cool in the refrigerator. Break into bite size pieces and store in a closed container.