Saute the chopped onion just until starting to brown.
Add the garlic cloves and continue sauteeing until the onion pieces are well browned.
Add the peas and cook, stirring, until heated through.
Pour in three cups of chicken bone broth.
Sprinkle in half a teaspoon of salt, a quarter teaspoon of pepper and the chili flakes.
Bring to the boil, lower the heat, cover and simmer for ten minutes.
Remove the pot from the heat, plunge in an immersion blender and process the peas until smooth (don't worry if the mixture appears too thick at this point).
Return the to the stove and, with the heat set to low, pour in more bone broth until you get the consistency of a thick but still pourable soup.
Taste, add more salt and pepper, if needed, then stir in a tablespoon of lime or lemon juice.
Taste again and, if the soup is still too sweet, stir in the rest of the lime or lemon juice.
Ladle the soup into bowls. Garnish, if you like, and serve.