Rosemary baked onions

Preheat the oven to 180°C/gas 5. Remove the papery outer layer of the onions, leaving their skins intact, then trim off their tops and bottoms.

Cut a cross in the top of each onion, slicing down to cut into four, but only three quarters of the way through, making sure the onions stay whole.

Place each onion on a square of foil and create a loose parcel that's open at the top. Cut 4 cloves garlic into 5 slices each, then push one slice into each of the cross cuts and one in the centre, pushing down to the core.

Do the same with the rosemary spigs, using one for each onion, breakingthe sprigs into smaller pieces.

Add balsamic vinegar, olive oil and a grind of pepper to each parcel. Then, bring up the corners of the foil and twist it at the top to seal. Bake for 45 minutes.