Mix flax seeds, chia seeds, sesame seeds, sunflower seeds, and pumpkin seeds in a bowl until well combined.
Blend half of the seed mixture until fine, then add it back to the remaining seeds and mix well.
Add Himalayan pink salt and spices like pepper, garlic powder, or smoked paprika to the seeds and mix again.
Pour 200 milliliters of boiling water over the seeds and stir immediately, allowing it to sit and thicken for 10 minutes.
Spread the seed mixture thinly on a parchment-lined baking tray using a spatula or the back of a spoon.
Cover the mixture with another piece of parchment and use a rolling pin to flatten it evenly.
Bake the seed crackers in a preheated oven at 160°C (320°F) for 25-30 minutes until golden around the edges.
Remove from the oven and cut into preferred shapes while still warm to prevent crumbling.
Allow crackers to cool completely; they will continue to crisp as they cool.
