Preheat oven to 350 degrees.
Line a 12x17-inch baking sheet with aluminum foil. Arrange the saltine crackers in a single layer on the sheet, covering the entire surface. Set aside.
35-40 Saltine Crackers
In a saucepan over medium heat, combine the butter and brown sugar. Stir continuously until the butter melts and the mixture comes to a boil. Let it boil for about 3 minutes, whisking constantly to prevent burning.
1 cup Brown Sugar, 1 cup Butter
Place the baking sheet in the oven and bake for 5 minutes, or until the toffee starts to bubble around the edges.
11 ounces Semi-Sweet Chocolate Chips
Remove the pan from the oven and immediately sprinkle the chocolate chips over the hot toffee. Let them sit for a few minutes to soften, then spread the melted chocolate evenly across the surface.
1/2 cup M&M, Sliced Almonds, Chopped Pecans or Walnuts
Sprinkle M&Ms, nuts, or your preferred topping over the melted chocolate.
Place the baking sheet in the refrigerator for at least an hour, or until the chocolate and toffee are completely set.
Once hardened, break the toffee into pieces and enjoy!