Preheat oven to 180C/350F/Gas 4 and line a cookie sheet with parchment paper or a silicone baking mat.

Place the butter and sugars into a large mixing bowl and cream together with a wooden spoon, spatula, or handheld mixer.

Add the egg, mint extract, and some green food coloring and mix to get the color you desire. Remember you can always add more color but not take it away!

Sieve the flour, baking soda, baking powder, cream of tartar and salt into another bowl and then add to the wet mixture. Stirring to combine into a dough.

Fold the chocolate chips and Lucky Charms marshmallows into the dough until evenly distributed.

Use a small ice-cream scoop to scoop even pieces of dough and roll into small balls. Place them 2-inches apart on the prepared cookie sheets.

Bake the cookies for 10 minutes.

Leave to cool for 2 minutes on the cookie sheet - you could press in some extra marshmallow pieces and chocolate chips if you like.

Transfer to a wire rack to cool completely before enjoying.