Mix together the potatoes, eggs, breadcrumbs and flour to form a smooth dough. Stir in the vegetables, season with salt, ground black pepper and nutmeg and shape into 8 burgers.
Mix the nuts together on a plate. Brush the burgers with the beaten egg and then roll in the nuts. Press the nuts on firmly and fry the burgers in hot oil until golden brown.
Slice the baguette into eight equal pieces and place on the grill. Rub with the garlic and drizzle with a little oil. Place the lettuce and tomatoes on the baguette slices, place a burger on top and garnish with the spring onions.