Put the buckwheat in a small pot with the water and pinch of salt, and bring to a boil. Turn down to simmer, covered, for about 5 minutes. Note: If you use untoasted buckwheat, it will take more like 20 minutes to cook after boiling.

Preheat the oven to 350 F.

Mix together the ground flax with the 1/4 cup water and leave to sit.

Mix together the seasonings in a large bowl, then add the cooked buckwheat and soaked flax and stir to combine.

Line the loaf pan with parchment paper to make sure you can get it out easily. Put the mixture into a loaf pan, and put in the oven. Halfway through baking, spread more tomato paste or ketchup on the top if you like.

Once the loaf is done, take it outof the oven, and let it cool for 10 minutes or so before taking it out of the pan and slicing.