2.Remove rind from lemon with a zester, into long thin strips. Squeeze juice from lemon; you will need 2½ tablespoons juice.
3.Combine rind, chilli, lemon thyme, garlic and extra virgin olive oil in a small saucepan over low heat for 5 minutes or until mixture is warm. Remove from heat; stir in juice. Season.
4.Place mushrooms on an oven tray. Drizzle with some of the lemon chilli dressing; season. Bake for 15 minutes or until mushrooms are tender.
5.Squeeze excess moisture from grated kumara. Combine kumara, flour and 1 egg in a medium bowl; season. Heat half the olive oil in a large frying pan over low-medium heat. Add a quarter of the kumara mixture, flatten with a spatula to form a 13cm (5¼-inches) round; cook for several minutes each side or until browned and cooked through. Transfer to a tray; cover with foil to keep warm. Repeat with remaining mixture to make four rösti in total, adding more olive oil to pan when necessary.
6.To poach eggs, half-fill a large deep frying pan with water, add vinegar; bring to a gentle simmer. Break 1 egg into a cup. Using a wooden spoon, make a whirlpool in the water; slide egg into whirlpool. Repeat with a second egg. Cook eggs 3 minutes or until whites are set and yolks remain runny. Remove eggs with a slotted spoon; drain on a paper-towel-lined plate. Keep warm. Repeat poaching with remaining eggs.
7.Drizzle remaining olive oil in a large saucepan over medium-high heat, add spinach; cook, covered, stirring occasionally, for 2 minutes or until just wilted. Season.
8.Divide rösti among plates; top with spinach, mushrooms and eggs. Drizzle eggs with remaining lemon chilli dressing.
If you don’t have a zester, you can finely grate the lemon rind instead. The secret to successful poached eggs is to use fresh eggs. As an egg ages, the white breaks down becoming runny and so doesn’t cling to the yolk as well. Check the cartons when you buy eggs and select one with the longest use-by-date.