Preheat a large soup pot over medium high heat with 2 turns of the pan of EVOO, about 2 tablespoons. Add the garlic, red pepper flakes, onion, salt and pepper, and cook stirring every now and then for 3 to 4 minutes. Add the escarole, working in batches to make room for all of it in the pot. Once the escarole is all in, season with some nutmeg. Add the beans and veggie stock and bring up to a bubble, then simmer for 10 minutes. Add the lemon zest, stir to combine.
Taste and adjust seasoning with a little more salt, pepper and nutmeg. Serve with some grated Parmigiano and crusty bread.