Stuffed Portobello mushrooms with caramelised Brussels sprouts

Polenta

• 6 fresh portobello mushrooms
• 240 g water
• 220 g full cream milk
• 2 tsp olive oil
• 2 dried bay leaves
• ½ tsp dried thyme
• 1 tbsp Vegetable stock paste (see Tips)
• 100 g polenta (see Tips)
• 1 - 2 pinches sea salt, to taste
• ½ tsp ground black pepper, to taste
• 100 g mascarpone cheese

Caramelised onion and Brussels sprouts

• 8 Brussels sprouts, cut into halves
• 1 garlic clove
• 120 g red onion, cut into halves
• 20 g unsalted butter
• 1 tbsp dark brown sugar
• 1 tbsp balsamic vinegar
• ½ tsp sea salt