Preheat the oven to 200ºC/400ºF/gas 6. Soak the farro or bulgar wheat in cold water for 20 minutes, then drain.
Meanwhile, slice the courgettes crossways into chunky crescents and put into a large roasting tray. Add the remaining vegetables and garlic cloves and toss together with a good splash of olive oil. Season well.
Spread the vegetables out in one layer if you can, as they’ll roast better this way – use 2 trays if you have to. Roast in the oven for 30 to 40 minutes, removing the trays from the oven and carefully shaking them every now and then, until the vegetables are cooked through and crisp around the edges. Sprinkle the vinegar over the vegetables as soon as they come out of the oven and set aside to cool. When cool, tip on to a large chopping board, add the fresh herbs and chop it all finely.
Place the farro or bulgar wheat in a large saucepan, cover with fresh cold water and bring to the boil. Simmer for 20 minutes or until tender, then drain well. Dress the farro or bulgar wheat with a good splash of olive oil and a squeeze of lemon juice, season with salt and pepper and toss with the chopped vegetables. Scatter the reserved fennel tops over the mix and serve.