Place the butter and cream cheese in your chosen microwavable mug. Microwave on HIGH for 20 seconds.
Add the remaining ingredients apart from the lemon curd/custard to the mug and mix well.
Drop the lemon curd/custard into the batter. Use the back of a fork or knife to push the curd into the middle of the batter until it is covered.
Microwave on HIGH for 1:20 seconds minute. Enjoy!
Please adjust the microwave cooking times according to the strength of your microwave.My microwave is pretty powerful and only requires 1 minute, but most standard microwaves may require the 1:20 as stated in the recipe.No microwave? No problem. Simply bake at 180C/350F in a cupcake case or muffin tray for 12 minutes.