Tarragon bread: In a blender combine the tarragon leaves with the eggs and blend on high until smooth. Add the remaining ingredients and blend on high for 30 seconds, until smooth. Strain the mixture and place into ISI canister. Charge twice and shake vigorously, refrigerate for a few hours.
Rillettes: Preheat oven to 160c. Dice pork into 2 cm x 2cm pieces and rub with salt & black pepper Place pork in medium casserole, bury herbs and garlic in diced pork Grind over plenty of fresh pepper Add water to dish until just covering pork, cover and bake in oven for approx. 3 hours or until its is swimming in its own juices and fat and the pork should be fork tender. Tip into a colander set over a bowl to catch the juices, place pork into separate bowl and shredded with two forks, spoon in some of the reserved juices and season well (rilettes are traditional really well seasoned). Spoon into preserving jars or clean containers and refrigerate.
To serve: Place a small amount of pork rillette in bottom of a flat round dish to a thickness of around 1 cm. shake the ISI canister really well and dispense enough tarragon bread mix to cover, microwave on high for 1 minute – it takes a little practise to work out how much tarragon bread mix your dish will need. Sprinkle chopped chervil & fennel & fennel pollen around edge of bread. Serve warm for guest to pinch bread and rillette as a canape.