Preheat the oven to 200C/400F/Gas mark 6.

Wash and dry the sweet potatoes.

Pierce each sweet potato several times with a fork.

Prick the sausages several times with a fork.

Arrange the sweet potatoes on a baking tray and the sausages on a wire rack over a baking tray.

Bake in the oven for 30-45 minutes, or until tender.

Heat olive oil in a large frying pan over medium heat.

Add the sliced onions and cook, stirring occasionally, until they start to brown (about 6 minutes).

Add the sliced garlic, fennel seeds, green beans, cherry tomatoes, and grapes to the pan.

Cook for another 6-8 minutes, stirring often, until the grapes and tomatoes begin to soften and caramelize.

Pour apple cider vinegar over the mixture and swirl it around the pan.

Turn off the heat and wait for the sausages and sweet potatoes to finish cooking.

Once the sausages and sweet potatoes are cooked, transfer the sausages to the onion-and-grape mixture.

Stir and cook over medium heat for 2-3 minutes until everything is sticky and well combined.

Place a baked sweet potato on each plate and cut it open.

Serve the sausage mixture next to the sweet potato.