Heat the olive oil in a large pot over medium-high heat. Add the chicken and sear until lightly browned.
Reduce the heat to medium and add the butter. Once melted, add the onion and cook for 5–7 minutes, stirring occasionally, until softened and translucent without taking on much color. Add the garlic and cook for another minute.
Pour in the white wine, scraping up any browned bits (the fond) from the bottom of the pot. Simmer until the wine has reduced by about half.
Add the chicken stock, cream and Parmigiano Reggiano rind, if using. Bring to a gentle simmer, then reduce the heat to medium-low. Cook uncovered for 12–15 minutes, maintaining a gentle simmer rather than a boil.
Add the lemon zest, fish sauce, sambal oelek and peas. Cook for 3–4 minutes, then add the baby spinach and stir until wilted.
Add the gnocchi and cook for 1–2 minutes less than the package directions. The gnocchi will continue to soften in the hot soup after it is removed from the heat.
Remove the pot from the heat. Stir in the grated Parmigiano Reggiano, lemon juice and parsley until the cheese has melted into the soup. Taste and adjust the seasoning with salt and freshly ground black pepper.
Ladle into bowls and finish with freshly grated Parmigiano Reggiano and chopped parsley, if desired. Serve immediately.
