Clean the cuttlefish (this may be done by the fishmonger) and cut into 2 cm wide strips. Do not salt!
Heat olive oil in as wide a pan as possible and briefly sauté the chopped garlic and chilli peppers. Add the cuttlefish and fry over high heat for about 10 minutes. The strips should be next to each other. Turn once. Deglaze with the wine, allow to evaporate. When the cuttlefish release liquid, reduce the heat and let everything simmer, covered, for 20 minutes.
Add the tomato paste and cook for another ten minutes. Increase the heat and add the (now probably cold) finished Swiss chard and cover and heat together.
Only add salt last, otherwise the cuttlefish will solidify.
Tip: Do not use too much tomato paste. It is more for the color. Under no circumstances should the tomatoes taste prematurely!