Preheat oven to 160 degrees celsius (fan-forced) and line a 20cm square tin with baking paper. Set aside.
Place the butter into a microwave-safe bowl. Heat for 1 minute.
Add the caster sugar and sifted cocoa powder and stir.
Heat in the microwave on 30 second bursts (50% power) until sugar dissolved and ingredients combined - stirring each time.
Allow to cool slightly.
Add the vanilla extract and the eggs and whisk until combined.
Sift the plain flour into the bowl and gently fold through.
Pour the brownie mixture into the prepared tin and bake for 25-30 minutes or until cooked through.
Leave in the tin to cool completely.
Thermomix Mehod
Preheat oven to 160 degrees celsius fan-forced (320 degrees fahreinheit). Line a 20cm x 20 cm square baking tin (8 x 8 inches) with baking paper. Set aside.
Place the butter into the Thermomix bowl. Melt for 3 minutes on 80 degrees, Speed 2.
Add the caster sugar and cocoa powder and mix for 10 seconds on Speed 4. Scrape down the sides of the bowl and repeat for a further 10 seconds. Allow to cool slightly.
Add the vanilla extract and the eggs and mix for 10 seconds on Reverse, Speed 4. Scrape down the sides and repeat.
Add the plain flour and mix for 5 seconds on Speed 4. Scrape the sides of the bowl and repeat.
Pour the brownie mixture into the prepared tin and bake for 25-30 minutes or until cooked through. Leave in the tin to cool completely.
Notes
RECIPE NOTES & TIPS:
Brownies continue to cook as they cool, so pull them out slightly underdone.
Use room temperature eggs to prevent the mixture from seizing.
Line the tin well for easy removal.
Let the brownie cool completely before slicing for neat edges.
Want a gooey centre? Bake for the lower end of the time range.
Store in an airtight container at room temp for up to 4 days.
Freeze slices in an airtight container for up to 3 months.