Heat the butter in a large pot over medium-low heat until melted. Stir in the onions, carrots, squash and garlic with a big pinch of salt and pepper. Stir in the dried thyme and oregano. Cook, stirring often, until the vegetables soften slightly, about 5 minutes.
Stir in the chicken. Pour in the chicken stock and bring the mixture to a boil. Reduce it to a simmer, cover and cook for 10 to 15 minutes until the squash has softened.
While the soup is simmering, make the dumplings. Stir together the flour, baking powder and salt. In a bowl, whisk together the ricotta and egg until combined. Add the ricotta mixture to the flour, and mix until it's all moistened and combined. It will be thick and almost like a dough. If it seems too thick (this will depend on your ricotta!) add a tablespoon of milk and stir. You don’t want to overmix.
Uncover the soup. Stir in the cream. Stir in the kale.
Scoop spoonfuls of the dumplings in the soup while it is simmering. Simmer for 10 to 12 minutes, then flip the dumplings over with a spoon. Simmer for 8 to 10 minutes more.
Taste and season the soup with more salt and pepper if needed. You can serve this with a dollop of ricotta on top or even stir some more ricotta into the soup.