1. Mix milk, soybean oil and 10 grams of caster sugar until the sugar melts
2. Mix low-gluten flour with barley flour, sieve, and then add to step one
3. Stir until there are no particles and a smooth state
4. Add the egg yolk and stir evenly into an egg yolk paste for later use
5. Add 30 grams of fine sugar to the egg whites and beat with an electric whisk until wet foaming (the egg beater has a small hook)
6. Take 1/3 of the beaten egg whites into the egg yolk paste and mix evenly
7. Then pour all the egg yolk paste into the remaining egg whites, stir evenly, and pour it into a baking pan lined with greased paper, spread evenly
8. Preheat the oven in advance, put it in the middle layer, heat up and down 170 degrees, bake for about 14 minutes
9. After the baked cake is out of the oven, immediately tear off the oiled paper and cover it again. The whipped cream and powdered sugar are mixed
10. After the cake is cool, cut off the four sides, spread whipped cream, and pile one end into a small hill, then roll up the cake
11. Keep in the refrigerator for about an hour before cutting into pieces
