Preheat your oven to 350°F (175°C) and line a baking sheet with parchment paper.
In a large bowl, cream together the softened butter and sugar until light and fluffy.
Beat in the egg and vanilla extract until fully incorporated.
Sift in the flour, cocoa powder, and baking soda, mixing until a soft dough forms.
Fold in the semisweet chocolate chips.
Roll the dough into small balls and place them on the baking sheet, flattening them slightly.
Bake for 10-12 minutes until set but still soft, then cool completely on a wire rack.
In a small microwave-safe bowl, combine caramels and heavy cream, heating in 20-second increments until smooth.
Once cookies are cool, spread a thin layer of chocolate frosting over each.
Drizzle the melted caramel over the frosting and sprinkle immediately with toffee bits to finish.