Heat a large soup pot over medium heat. Add the oil, onion, carrot, thyme, and rosemary. Cook until the onions are softened and starting to brown (about 5 minutes).
Stir in the garlic and Swiss chard and continue to cook until aromatic (about 30 seconds). Add the stock, tomatoes, and acini de pepe. Bring to a simmer.
Season with salt and pepper and cook until the ancini de pepe is al dente (about 10 minutes). Taste and adjust seasoning.