Whisk the egg, butter and sugar together.
Add the remaining ingredients and mix until mixed through.
Pour mixture into an airtight container and allow to rest in refrigerator overnight.
Fill greased muffin tins 2/3 full.
Bake in a preheated oven at 180°C for 20 - 25 minutes, or until muffins spring back when pressed with finger.
Remove from heat and allow to cool slightly in tins before turning out onto a cooling rack.
Serve muffins halved with low-fat cottage cheese and strawberries.