A few heaped dessertspoons of sugar-free fruit spread (I took the easy route and stole some of my husband's St. Dalfour fruit-sweetened raspberry jam. A homemade version, like this recipe, will work great too).
Optional topping (my addition): some sliced almonds
Pastry base: Oil a 10" tart dish and set aside. Briefly mix the rice flour, tapioca flour and ground flaxseeds together in a bowl. Add the coconut oil (melt first), rice syrup and vanilla. Mix with a spoon. Once it has started to combine together nicely, use your hands to knead and press it all together until you have one large ball of pastry (if it's cold, the warmth of your hands will soften the dough and make it pliable). Flatten the dough into a disk (or roll out a little if you prefer), and place in the prepared tart pan. Use your hands to "massage" the dough and shape it into a tart shell, evening out any gaps or cracks as needed. When done, put the tart pan in the fridge while working on the next step.
Cake topping: Preheat oven to 350F (or gas mark 4). Mix all dry topping ingredients together in a mixing bowl. Mix all the wet ingredients in a jug. Pour the wet ingredients into the mixing bowl and thoroughly mix in with the dry (a bit of a "fizz" is normal at this stage).
Assembly: Take the tart pan out of the fridge. Spread an even layer of fruit jam over the base of the tart crust. Pour the cake mixture into the pastry base over the fruit spread (or spoon it on top if it turns a little thick if it's cold in your kitchen). (I topped mine with some sliced almonds at this point).
Baking: bake for 35 minutes in a pre-heated oven. Remove and cool on a wire rack completely so as to avoid crumbling. Enjoy!