Preheat oven to 200°C. Line a large oven tray with baking paper.
Remove the outer leaves from the Brussels sprouts and trim the ends. Cut in half.
Cut the broccoli into florets.
Place the vegetables onto your prepared oven tray with the bacon and garlic. Season well with salt and pepper and pour over the olive oil. Toss everything together so the vegetables are well coated.
Cook for 20 minutes, turning every now and then. Add the balsamic vinegar, toss through to evenly coat and cook for a further 5–10 minutes or until vegetables are tender.