Preheat the oven to 350°F. Line a baking sheet with parchment paper and set aside.
Cream the butter and sugars. In a large bowl, use an electric mixer to beat the butter, light brown sugar, and granulated sugar until smooth and fluffy.
Add the wet ingredients. Mix in the eggs, corn syrup, and vanilla extract until fully incorporated.
Combine the dry ingredients. In a separate bowl, whisk together flour, salt, and baking soda.
Form the dough. Gradually add the dry mixture to the butter mixture, mixing until a soft dough forms.
Add mix-ins. Gently fold in 1 cup chocolate chips, ½ cup toffee pieces, and ½ cup crushed saltine crackers. Stir just until combined.
Shape the cookies. Roll the dough into 2-tablespoon-sized balls and place 6 at a time on the prepared baking sheet, spacing evenly.
Bake. Bake for about 15 minutes, or until the edges are golden brown and the centers are set but still slightly soft.
Cool. Allow cookies to cool completely on a wire rack.
Melt the chocolate. In a microwave-safe bowl, melt the remaining 1 cup of chocolate chips in 30-second intervals, stirring until smooth.
Decorate. Spread a layer of melted chocolate over each cooled cookie, then top with Christmas sprinkles, additional toffee bits, and remaining crushed saltine crackers.
Set and serve. Let the cookies cool completely until the chocolate hardens before serving or storing.