Makes about 2 dozen
30 saltine crackers
1/2 cup dark brown sugar
1 stick (8 tablespoons) butter
1 bag (12 ounces) chocolate chips
1/2 of an 8-ounce bag Heath Bar bits
Adjust oven rack to lower-middle position and heat oven to 350 degrees. Grease a 9- by 13-inch rimmed cookie sheet with vegetable cooking spray. Line pan bottom and up and over the long sides with heavy-duty foil for easy removal. Grease foil with vegetable cooking spray and then line with crackers, cutting as necessary to fit the pan.
Heat butter and brown sugar in a medium saucepan over medium heat, stirring frequently, until simmering. Pour brown sugar mixture evenly over saltines and working quickly, use a spatula to spread it.
Bake saltines until bubbly and golden brown, about 10 minutes. (Watch carefully to make sure it doesn't burn) Remove from oven and sprinkle chocolate chips over hot crackers; let stand 3 minutes and then spread the melted chocolate evenly over crackers with a spatula. Sprinkle with Heath Bar Bits. Freeze until firm. Using foil handles, remove bar from pan. Break into pieces and serve.