Preheat the oven to 140°C.
Heat a casserole dish and add oil, octopus, tomatoes, garlic, rosemary, and chilli.
Braise in the oven for 2 hours, checking occasionally to prevent sticking.
Boil potatoes in salted water for 10-15 minutes until tender.
Drain the potatoes and set them aside.
Wilt wild garlic and agretti in a frying pan with a little oil.
Mix the garlic, agretti, cucumber, chicories, and potatoes in a bowl and season.
Cook anchovies in a frying pan with oil until they dissolve.
Add the remaining dressing ingredients and whisk together.
Mix the dressing into the salad just before serving.
Serve the octopus alongside the prepared potato salad.