Preheat the oven to 150 C / Gas 3. Grease and flour a small loaf tin.
Place the mixed fruit, cherries, sugar, margarine, bicarbonate of soda and cold tea in a large pan and bring to the boil. When the margarine has melted, take off the heat and allow to cool for about 15 minutes.
When the mixture has cooled, add the plain flour, self-raising flour, eggs, baking powder and mixed spice and mix well. Pour into the loaf tin.
Bake until skewer inserted in the middle comes out clean, about 2 hours. Leave in tin for 5 minutes, then turn out on to wire tray to cool.
I have made this tea cake a couple of times now and it has been delicious on each occasion. I have fan oven and found I didn't need the full baking time. Keeps very well (if not immediately eaten!) and is now my 'go to' tea cake recipe. - 10 Aug 2014