For the dough, mix all the ingredients for the dough in a large bowl until evenly mixed. Turn the dough out onto a lightly floured work surface and knead for about five minutes, or until smooth.
Place the dough back in the bowl, cover with cling film and leave to rest for 30 minutes at room temperature until doubled in size.
Tip the dough onto a lightly floured work surface and roll to form into an even cylinder 30cm/12in long. Cut into eight equal parts and form each into flat, 3-5mm thick rounds. Place onto a lightly floured peel or an upturned baking tray.
Preheat the oven to 220C/425F/Gas 7 and place a baking stone into the oven.
To top the breads, lightly brush the top of each flatbread round with the melted butter and scatter a mixture of the onion seeds, ground cumin and sea salt over the surface.
Using the peel or upturned baking tray, transfer the flat breads to the oven and bake directly on the baking stone for 10 minutes.
Remove the bread from the oven and leave to cool on a wire rack.
For the baked cheese ‘fondue’, preheat the oven to 180C/350F/Gas 4.
Remove all the packaging from one of the cheeses and place it back in the box. Place the lid under the base for extra support. Score the top of the cheese in a lattice pattern.
Using a spoon, push the crushed garlic, rosemary and chilli flakes into one of the cheeses. Push the truffle slices into the other cheese.
Place onto a baking tray and bake in the oven for about 30 minutes, or until the cheese starts to go wobbly in the middle.
Remove from the oven and allow to rest for five minutes. Serve scooped up with the flatbreads.