Mississippi Mud Cake

I had a few enquiries about the cake Joshua made for me last week. I thought it might be best to post it straight up here - so if you're needing a delicious cake, this is your go-to place! I asked Joshua for the recipe, he sent it through to me, and ta-da!
The recipe is from The Australian Women's Weekly "Classic Cakes".

Mississippi Mud Cake

Cake mixture:
250g butter, chopped
150g dark eating chocolate
2 cups (440g) castor sugar
1 cup (250mL) hot water
1/3 cup (80mL) coffee liqueur (I used Baileys because I didn't have any coffee liqueur)
1 tbl spoon instant coffee
1 1/2 cups (225g) plain flour
1/4 cup (35g) self raising flour
1/4 cup (25g) cocoa powder
2 eggs, beaten lightly

1. Preheat oven to 160 (140 fan forced). Grease deep 20cm round cake pan, line with baking paper.

2. Combine butter, chocolate, sugar, the water, liqueur and coffee granules in medium saucepan. Using wooden spoon, stir over low heat until chocolate melts.

3. Transfer mixture into large bowl; cool 15 mins. Whisk in combined sifted flours and cocoa, then egg.  Pour mixture into prepared pan.

4. Bake cake for about 1 1/2 hours.  Stand cake in pan 30 minutes before turning top-side up onto wire rack to cool.

5. Meanwhile, make dark chocolate ganash, spread over cake.

Dark chocolate ganash:
1/2 (125mL) cup cream
200g dark eating chocolate, chopped coarsely

Bring cream to the boil in small saucepan.  Pour hot cream over chocolate in medium heatproof bowl; stir until smooth.  Stand at room temperature until spreadable.