Step 1: Spiced Rum Whoopie Pie Recipe.
Cream 110g butter with 180g caster sugar. Add two eggs, one at a time, and then add 75ml milk and 30ml rum. Mix well.
Add 1 tsp each of mixed spice and ground ginger, plus a pinch of salt and 250g gluten free self raising flour mix. That's right - they're gluten free, too!
Step 3: Shape the Whoopie Pi
Start with the top bar, this is the easiest part. Keeping the nozzle close to the paper will help to control the shape. Don't be afraid to go back and double over any parts that look like they need thickened up a little, especially around the joins, or to use a teaspoon to reshape any bits that haven't come out right.
Make sure to leave space between them and make the lines thin enough so that they won't touch even after they puff up in the oven. Also remember to pipe half facing backwards, so that you can pair them up.
When handling the shapes, take care to hold them by the top bar and be gentle. Don't lift them in such a way as to press the two 'legs' together, this will cause stress and possible breaking. The weakest points are the joins between top bar and vertical legs, be wary of them, or suffer the consequences.
Applying the filling is best done by holding one pi flat on your hand, and using a piping bag to pipe the filling on top. You can also use a teaspoon - keep the spoon full and use the bowl to spread the filling, it's more forgiving than spreading with the back of the spoon. Lightly press the other pie on top when you're done - the filling should stick them together without too much pressure.