Sweet potato brownies with espresso topping

This sweet potato brownie recipe with espresso icing is featured in Dr Joanna McMillan's book - Brain Food. As well as being a delicious chocolate treat, cocoa is rich in antioxidants.
Sweet potato browniesJohn Paul Urizar
16 brownies
1H 30M

Dr Joanna McMillan says:

These days, I’ve noticed there’s a trend for everything cocoa to suddenly be called cacao. Technically though, cacao is the unfermented, fresh seed; once fermented, it becomes cocoa, although some argue the word cocoa came from a misspelling of cacao. Cocoa powder (pure, non-sweetened, that is) is a great source of polyphenols – an antioxidant that may help to protect cognitive function as we age.

BRAIN FOOD by Dr Joanna McMillan (Bauer Books) rrp: $35

Available at and all good bookstores.


Espresso icing


1.Place sweet potato in a medium saucepan with enough cold water to cover; bring to the boil. Cook, covered, for 15 minutes or until soft. Drain; return to saucepan. Mash until smooth.
2.Meanwhile, preheat oven to 180°C/350°F. Lightly grease a deep 20cm (8in) square cake pan; line base with baking paper.
3.Combine ground linseeds and 1/2 cup (125ml) hot water in a small heatproof bowl. Stand for 10 minutes.
4.Chop chocolate coarsely. Place chocolate, sugar, vanilla, 1/4 cup (60ml) water and sifted cocoa in a large heatproof bowl over a saucepan of simmering water. Stir until melted and smooth. Remove from heat; stir in mashed sweet potato. Add linseed mixture, almond meal and soda; mix well.
5.Pour mixture into pan. Bake for 1 hour or until firm to the touch. Cool slightly in pan.
6.Make espresso icing: Dissolve coffee in 1 tablespoon boiling water. Chop chocolate. Place chocolate in a small saucepan with syrup, sugar, vanilla and coffee; cook, stirring, over low heat until melted and smooth. Remove from heat; stir in sifted cocoa.
7.Spread top of brownie with icing and scatter with flaked almonds; stand until set. Cut into 16 squares to serve; dust with a little extra cocoa if you like.

Brownie will keep, stored in an airtight container at room temperature, for up to 3 days or can be frozen for up to 3 months.


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