Microwave mug cake - Good Food Middle East

Ingredients

• 4 tbsp self-raising flour
• 4 tbsp caster sugar
• 2 tbsp cocoa powder
• 1 medium egg
• 3 tbsp milk
• 3 tbsp vegetable oil or sunflower oil
• a few drops of vanilla essence or other essence (orange or peppermint work well)
• 2 tbsp chocolate chips, nuts, or raisins etc (optional)