Why not treat yourself to a small indulgence from time to time. There are 2 options here to choose from, the lower calorie version and the higher calorie mass gainer version.
Lighter Calorie Version 
1 scoop Protein Matrix Chocolate
1 tbsp. Nutella 15g
4 Ice cubes
250ml cold water
Makes one serve
Method
Blend and enjoy, can be made in the morning and taken to work and put in fridge until ready to consume.
Nutritional Information per serve:
P: 24.8
F: 5.7
C: 10.9
Cal: 198
Muscle Gain Version
2 scoops Protein Matrix Choc Hazelnut
2 tbsp. Nutella
1 large Banana
4 Ice cubes
300ml cold milk
Makes one serve
Method
Blend and enjoy, you can always drop the Protein powder serve down to 1 scoop and still get enough protein, depending on how much muscle mass you are needing to nourish.
Nutritional Information per serve:
P: 61.3
F: 12
C: 79
Cal: 626