Custard Cream

I have just made it just now for cream puffs filling. The recipe was taken from MR by Honey. I was curious to try this version as it uses whole egg unlike the typical custard cream recipe which uses only egg yolks. This can be made ready in just 10 minutes! However, there is a bit of egg smell... I added vanilla essence to solve the problem.

(Enough to fill 20 puffs)
INGREDIENTS:
1 tbs Flour
1 tbs Cornflour
4 tbs Sugar
200cc Milk
1 Egg (Large) or 2 Egg Yolks
1 tsp Vanilla Essence (not in the original recipe)
1 tbsp Butter

METHOD:
1. Mix all ingredients except butter.
2. Microwave for 5 minutes, stirring every 1 min interval.
3. Lastly add Butter.