Stir instant coffee powder into warm milk until dissolved, then mix in your vegetable oil and vanilla extract.
2. Step
In a separate bowl, whip egg whites and add the sugar in three parts until it forms a stiff meringue. To this, slowly add the egg yolks, one at a time, while mixing with a whisk.
3. Step
Sift the flour and cocoa powder into the bowl and fold/mix the batter with a rubber spatula until fully incorporated.
4. Step
Rub a rice cooker well with cold butter or oil and add batter. Stir with a chopstick to release any big air bubbles.
5. Step
Cook the batter in the rice cooker for 50 minutes, or until cooked through.
