Process the chicken, fennel fronds, dill sprigs and parsley sprigs in a food processor until finely chopped. Season with salt and pepper.
Using slightly damp hands, roll 1½ tbs of chicken mixture into a ball. Transfer to a plate. Repeat with remaining mixture. Place in the fridge for 30 mins to chill.
Meanwhile, combine the teff and paprika in a medium saucepan. Pour in half the stock and 1 cup (250ml) water. Place over high heat and bring to the boil. Reduce heat to low and cook for 15-20 mins or until teff is tender.
Add half the oil to a frying pan over medium-high heat. Add the meatballs and cook, turning often, for 3-5 mins or until golden brown. Transfer to a plate.
Add remaining oil to the pan. Add onion and cook, stirring, for 5-8 mins or until golden. Add garlic and cook for 1 min or until aromatic. Add the sliced fennel and mushroom. Cook, stirring, for 5 mins or until vegetables are tender. Pour over the remaining stock. Bring to the boil. Reduce heat to low. Add teff mixture and combine.
Arrange meatballs over the teff. Cook, covered, for 15-20 mins or until heated. Set aside, covered, for 10 mins to rest.
Meanwhile, to make the shaved fennel salad, combine the fennel, parsley, lemon juice, lemon zest and olive oil. Top meatballs with a bit of salad. Transfer remaining salad to a serving bowl and serve with meatballs.