Put the cake flour and sugar in a heatproof bowl and mix. Combine the milk (or soy milk). Add the eggs and mix well.
Cover loosely with plastic wrap, and microwave at 500w for 2 minutes 30 seconds. (If using soy milk, see Step 4.) Mix well with a small whisk or 4 chopsticks held together. Microwave for another 2 minutes.
Repeat the microwave-mixing steps while observing how thick the custard is. (If the lines made by the whisk disappear as soon as you move it, the cream is still too thin.)
When I made the custard cream with natural soy milk, it thickened quickly. Using 2 medium sized eggs and a 500w microwave, it took just 2 minutes of microwaving x 2 times, 1 minutes x 1 time, 30 seconds x 1 time.
Using 2 medium sized eggs and regular milk, after Step 2, it took 1 minute of microwaving x 2 times, 30 seconds x 4 times.
Shake in vanilla essence and mix to finish.
Keep microwaving and mixing until surface firms up. When mixed, the cream should feel very thick. When you scoop it up with a whisk it should form soft peaks, and the cream should slowly with a plop.
Keep in mind that the pastry cream will thicken even more when cooled, so stop cooking just before it reaches the perfect, desired consistency. Keep mixing well to form a cohesive, smooth cream.
If you use half the amount of ingredients ＊: Microwave for 2 and a half minutes once, then microwave for 1 minute x 2 times to finish. When you want a little bit of pastry cream to sandwich in bread and so on, half the amount is convenient.
This is a failed example: It's made with milk, and microwaved for 2 minutes x 3 times. It has lots of tiny lumps. You need to heat it carefully and mix it well to avoid this.
When using this cream for cakes or tarts, it will drip when you cut the cake or tart if the consistency is too liquid, so I recommend making it on the stiffer side.
How about putting this pastry cream in a tart base for an easy tart (Recipe ID: 1006990)?
Story Behind this Recipe
I don't like having leftover egg whites. I also don't like making custard in a pan, since I think it will get burnt. I referred to several recipes for custard instructions, and after several experiments, I came up with this recipe which uses whole eggs and also makes just the right amount for an 18 cm tart.
I use a small whisk that I got in a 100 yen shop. If you don't have a whisk like that just use 4 chopsticks held together. If you use soy milk, the pastry cream will stiffen faster (See Step 4). The microwave time will vary on your microwave oven. If it's your first time making this, and/or you have a microwave that has a capacity higher than 400w, please try shortening the cooking times.