In a large dutch oven or heavy pot, heat 1 tablespoon olive oil on medium-high. Add onions, carrots, scallions and red pepper. Toss together to sautee briefly then add garlic.
Add chicken stock and bay leaves. Raise heat to high and bring to boil. Add salt and pepper then add orzo. Turn heat to med-low and simmer for 10 minutes or until orzo is tender. Stir in chicken.
In a medium bowl, whisk together lemon juice and eggs. While whisking add 2 ladles of broth from pot (this will temper eggs). Once combined add sauce to soup and stir in spinach. Remove from heat immediately.