Preheat the oven to 180 degrees C. Prepare a 2lb loaf tin by lining it with a loaf tin liner or greaseproof paper.
In a large bowl, mix together the butter and sugar until pale and smooth.
Crack the eggs into the bowl one at a time, beating between each one to make sure they are fully combined.
Gently fold in the flour. Add the mango and coconut and stir just until they are evenly distributed.
Spoon the batter into the cake tin. Transfer to the oven and cook for 50-60 minutes, until risen, golden and a skewer inserted into the middle comes out clean.
Leave to cool in the tin for 10 minutes before slicing.