Measure out 100 grams of sugar.

Crack the egg into a bowl, ensuring it weighs around 57-58 grams with the shell.

Beat the sugar and egg together for about 5 minutes until well combined.

Let the mixture rest for 10 minutes until it becomes foamy.

Ensure that the sugar has dissolved sufficiently during this resting period.

Add 1/4-1/2 tsp salt to the mixture.

Stir in 1/2 tsp vanilla extract.

Add 50 grams of cooking oil to the mixture and mix well.

Sift in 25-30 grams of unsweetened cocoa powder and mix until fully incorporated.

Sift in 40 grams of all-purpose flour and mix until just combined.

Use a brownie pan measuring 13x13 cm or 10x15 cm.

Preheat the oven to 160-170°C (320-340°F) for 10 minutes.

Pour the batter into the prepared baking pan and spread it evenly.

Bake in the preheated oven at 160-170°C (320-340°F) for 20-25 minutes.

Check for doneness by inserting a toothpick into the center; it should come out with a few moist crumbs but not wet batter.

Allow the brownies to cool completely in the pan before removing them.

Once cooled, cut into mini brownies and serve.