Heat oven to 200C/180C fan/gas 6. Slice the squash into 3cm pieces. Place on a large, greased baking tray and drizzle with 1 tbsp of the oil. Season well and roast for 25 mins or until golden.
While the squash is roasting, make the vinaigrette. Heat the remaining oil in a small pan. Add the garlic, keeping the heat low, and cook until golden. Remove from the heat and add the vinegar and honey. Return to the heat for 1 min, whisking until the vinaigrette becomes syrupy, then set aside.
To serve, arrange the rocket and mozzarella on 4 plates. Add mint to the vinaigrette. Divide the squash between the plates and drizzle with the vinaigrette.