Celeriac puree with balsamic shallots

Ingredients

• 6 round shallots, peeled and quartered
• 1 tablespoon olive oil
• 1 tablespoon balsamic vinegar
• 1 sprig fresh thyme
• Salt and ground black pepper to taste
• 500ml water
• 250ml whole milk
• 1 tsp salt
• 1 large celeriac about 600g total, peeled and cut into 2-inch cubes
• 2 tablespoons butter
• Ground black pepper to taste
• 1 portion of balsamic shallots