Slow cooked beef pot roast

Ingredients

• 10g dried porcini mushrooms
• 1 tablespoon olive oil
• 1.5kg topside beef roast
• 1 brown onion, thinly sliced
• 2 sticks celery, coarsely chopped
• 200g Swiss brown mushrooms, halved
• 200g mushroom cups, halved
• 1 garlic clove, crushed
• 500ml beef stock
• 1/2 cup (125ml) white wine
• 2 tablespoon tomato paste
• 6 thyme sprigs
• 8 baby carrots, peeled
• Mashed potato, to serve
• Steamed green beans, to serve
• Thyme sprigs, extra, to serve