Pat dry the Whole Chicken, trim any excess fat, and season lightly with Fine Sea Salt.
In a large stockpot, heat a splash of Olive Oil over medium heat and sauté chopped Onion, diced Carrots and sliced Celery until they begin to soften, about 5–7 minutes.
Add the Whole Chicken to the pot and pour in enough Water to cover the bird by 1–2 inches; toss in Bay Leaves, a few Black Peppercorns and a pinch of Fine Sea Salt. Bring to a gentle boil, then reduce heat and simmer, partially covered, for 1 to 1½ hours until the chicken is tender.
Carefully remove the chicken from the pot and set aside to cool slightly. Strain the broth through a fine sieve back into the pot, discarding solids, and skim off excess fat if desired.
When cool enough to handle, shred the chicken meat and discard bones and skin. Return the shredded chicken to a bowl and set aside.
Bring the strained broth to a simmer and add the White Rice. Cook until the rice is tender, about 12–18 minutes depending on rice variety.
While the rice cooks, make the avgolemono: in a medium bowl whisk the Eggs until frothy, then whisk in the juice of the Lemons until smooth.
Temper the egg-lemon mixture by slowly adding 2–3 ladlefuls of hot broth into the bowl while whisking constantly, then gradually whisk the warmed egg mixture back into the pot of soup.
Stir gently off the heat (or over the lowest possible heat) until the soup becomes slightly thickened and silky—do not boil or the eggs may curdle. Return the shredded chicken to the pot to warm through.
Taste and adjust seasoning with Fine Sea Salt and freshly ground Black Pepper. Serve the kotosoupa hot with extra lemon wedges on the side for squeezing.
