Put the porter (stout), dried fruit, peel, cherries, sugar and bicarbonate of soda in a large saucepan.
Heat gently until the butter has melted and the sugar has dissolved.
Bring to the boil for 10 minutes. Stir the mixture occasionally so it doesn't stick to the bottom of the pan.
Remove the pan from the heat and leave to cool (about 20 minutes)
Heat the oven to 180C/170C Fan/350F
Grease and line a 22cm/9 in square cake tin.
Add the eggs, flour and baking powder and stir to mix thoroughly.
Put the cake mixture into the tin and bake for about 1 hour 10 minutes. Check the cake after 1 hour as not all ovens are true to temperature.
The cake is ready when it has risen and is firm to the touch.
Remove the cake from the oven and leave to cool in the tin. When cold remove it from the tin and take off the parchment paper.
You can cut and eat the cake as soon as it is cold. However, Irish Porter Cake gets even better if you wrap it in foil and store it in an airtight tin for 2-3 days before eating.
Serve in slices with or without butter.