Preheat your oven to 350°F (175°C) and line a muffin tin with cupcake liners.

In a large mixing bowl, whisk together the flour, sugar, baking powder, and salt until well combined.

In a separate bowl, cream together the unsalted butter until fluffy, then add in granulated sugar gradually and mix until light and well-blended.

Add the eggs one at a time to the butter-sugar mixture along with the vanilla extract, mixing until smooth.

Add the dry ingredient mixture to the wet ingredients alternately with the milk, mixing gently until just combined, then fold in toffee bits.

Divide the batter into the muffin tin, filling each liner about ⅔ full and bake for 18-20 minutes until golden brown.

Allow the cupcakes to cool in the tin for about 5 minutes before transferring them to a wire rack to cool completely.