Mix together the dry ingredients (flours, flax, psyllium husk, salt, bicarbonate of soda, milk powder, herbs and yeast) in an airtight container and shake vigorously to blend.
Line a couple of baking trays with good non-stick baking paper (or if you want to make as a 'round', base-line two 9 inch round baking tins).
In a large bowl, lightly whisk together the eggs, oil, honey and lemon juice to combine.
Add the hand-warm water and whisk through with the other wet ingredients. It should foam well on the top as it is whisked.
Next, add the dry ingredients and beat well to blend (preferably using an electric whisk with a dough hook attachment). If you don't have a dough hook, use a sturdy silicone/wooden spoon and beat hard until very well blended. The mixture should look like porridge when done.
Place the bowl to one side and leave to stand untouched for a full 10 minutes. This is important and will enable the flours to absorb the liquid and hydrate fully.
While the dough hydrates, grate the cheddar and mix with the grated mozzarella. Set aside.
After the dough has hydrated, beat the mixture hard again (with dough hook or spoon) until stiff and holding its shape. The dough ‘batter’ will resemble very thick porridge and will hold its shape. Set aside.
Rolling and filling the dough
Lay a large piece of good quality non-stick baking paper on the counter-top to work on.
Lightly oil the surface of a large rolling pin.
Preferably wearing close-fitting vinyl food gloves, lightly oil the hands with a tiny drop of olive oil.
Divide the dough into two halves. Take the first half and gently work and knead in your hands until it becomes a smooth dough.
Place the kneaded piece of dough on the baking paper and flatten into a rough rectangle shape.
Using the oiled rolling pin, roll the dough into a rectangle approximately 35 cm x 25 cm (14 inches x 10 inches). If the pin starts to stick, rub a drop more oil into the pin's surface.
Using the back of a spoon, spread half the (preferably drained) pesto across the whole surface of the rolled dough.
Sprinkle half the cheese across the top, leaving a 2 cm (1 inch) border clear of extra toppings down the straightest long side. This will be the join.
Roll the filled dough into a spiral
Turn the rectangle on the baking paper so that the long 'un-topped' edge is closest to you.
Turn the opposite side of the dough over on itself by about 1½ cm (½ inch) all the way along. Support the turn by pulling up the back of the baking paper to hold it in place.
With the help of the baking paper, continue to roll the dough over itself into a spiral as tightly as possible, pulling the baking paper to help you as you go. Push the last edge into the dough roll to hold it together, but don't smooth as you may wish to further tighten each roll after cutting.
Cutting the dough into rolls
Next, cut the spiralled dough sausage into 9 equal pieces. If the ends are particularly uneven, these can be trimmed off first as preferred.
To cut, use a very sharp knife that has been lightly rubbed with oil, or a piece of baker's twine/string. Mark out nine even pieces by scoring the top before you start. Then cut through one by one.
If having cut the dough, the spirals look like they need to be tighter, take each in turn and (while on the baking paper), carefully loosen the join and unroll, re-rolling more tightly. Use hands to hold the filling into the sides as you roll, so that it doesn't get lost.
Carefully transfer the dough pesto rolls to a prepared baking sheet. Leave a reasonable gap (a couple of cm) between each for expansion when they rise. Arrange in rows to bake on a baking sheet or in a round tin, place one roll centrally and the others evenly round the sides.
Lightly drape a large piece of clingfilm over the dough rolls (be sure the rolls are not restricted) and set to one side.
Repeat the process for the second half of the dough and fillings
Repeat the kneading, rolling and filling process with the remaining dough and filling ingredients. When transferred to the baking sheet/tin, cover with clingfilm as instructed above.
Proving the pesto rolls
Place the trays in a warm place to prove for about 45 minutes to an hour (dependent on room temperature), until the dough rolls are nearly double in size. (If the room temperature is very cold, you can speed the process by placing the tray over a bowl of steaming (but not boiling) water.
Egg-wash and decoration
While the rolls are proving, prepare the egg-wash by lightly beating an egg with a little milk.
Pre-heat the oven to 190 C/375 F/Gas 5. Be sure to place a heat-proof dish at the bottom ready to add boiling water before baking (boil a kettle in advance). OR set the oven to steam at three x 5 minute intervals once the rolls are ready to bake.
When the dough has risen, lightly brush the rolls with egg-wash.
Bake the rolls
Just before baking, carefully fill the heat-proof dish with boiling water (or check the oven's steam setting) and then place the dough buns into the oven.
Bake for between 20 to 25 minutes (approx)... possibly more depending on the size of rolls, until golden.
Remove from the oven and transfer the rolls to a wire rack to cool.
Can be eaten warm or cold.
Store in an airtight bag at room temperature or freeze on the day of making.
* Note: nutritional information is an estimate & may vary according to portion size/ingredient variants.Yeast - The yeast used for this recipe is an INSTANT yeast. If mixing up the dry ingredients ahead of time, do not add the yeast until ready to bake as the salt will cause the yeast to deteriorate.If unable to tolerate buckwheat, this can be substituted for an alternative protein-rich flour such as oat or millet flour.You can use warm liquid milk to replace the water (at the same volume as the water) and leave out the milk powder if you are unable to find milk powder, although milk powder is better.