Savory egg custard

Ingredients
- 1 egg (Note: I chose to use quality organic cage-free egg since the ingredients used are few and basic) - 1/8 cup chicken stock (not more than half of the quantity of beaten egg mixture) - bunashimeiji mushrooms, a countable few
Instructions
1. Whisk egg well, and sieve to remove any remaining egg white strands 2. Add chicken stock to the beaten egg mixture. Stir to combine and DO NOT whisk again 3. Add mushroom to custard mixture 4. Steam over simmering fire or heat (DO NOT boil) till custard sets 5. Serve with a dash of sesame oil on top