Mix all ingredients together and let sit for 10 minutes as chia seeds swell.
Spoon ½ the mixture onto the centre of a sheet tray sized piece of baking paper. Place another piece of paper on top and roll out the mix using a rolling pin till about 3mm thick.
Using a knife, cut into desired shapes, taking care to just press the knife into the mix, not moving the knife back and forth through the dough (or it will tear.)
Bake at 160 C/325 F fan forced for approx 10-15 minutes. Turn over and break along cut lines and return to the oven for a further 10-15 minutes or until baked through and thoroughly dried out.
Allow to cool before storing in an airtight container for approximately 2 weeks.
Variations
You can switch the sesame seeds, pumpkin seeds, pepita seeds or poppy seeds for other seeds in the same quantities.